KR20170018075A - Pressure sensitive adhesive composition including ultraviolet light-absorbing oligomer - Google Patents

Abstract

상기 식에서, R¹은 수소 또는 메틸이고, R²는 4 내지 20개의 탄소 원자를 갖는 알킬이다. 조성물을 포함하는 물품이 개시된다. 예를 들어, 배리어 필름 및 조성물을 포함하는 조립체가 또한 개시된다.A composition comprising a pressure sensitive adhesive and a blend of ultraviolet light-absorbing oligomers. The oligomer has a first divalent unit having a pendant ultraviolet absorber and a second divalent unit represented by the formula:
(I)

Wherein R ¹ is hydrogen or methyl and R ² is alkyl having 4 to 20 carbon atoms. An article comprising a composition is disclosed. For example, an assembly comprising a barrier film and a composition is also disclosed.

Description

PRESSURE SENSITIVE ADHESIVE COMPOSITION INCLUDING ULTRAVIOLET LIGHT-ABSORBING OLIGOMER [0002]

Cross reference to related application

This application claims priority to U.S. Provisional Application No. 62 / 017,666, filed June 26, 2014, and U.S. Provisional Application No. 62 / 017,021, filed June 25, 2014, Which is incorporated herein by reference in its entirety.

It may be desirable to incorporate an ultraviolet absorber (UVA) into the material exposed to ultraviolet (UV) radiation, for example, to protect against UV degradation. Some UVA can be dispersed in some compositions but can sometimes be lost due to volatilization or migration to the surface. A covalent incorporation of UVA into a pressure sensitive adhesive (PSA) composition has been proposed (see JP2012188620, published Oct. 4, 2012). Certain copolymers prepared from monomers with UV absorbers are described for inclusion in PSA compositions (see JP2000123621, published April 28, 2000).

The present invention provides a composition comprising a pressure sensitive adhesive and an ultraviolet light-absorbing oligomer, wherein the ultraviolet light-absorbing oligomer has a first divalent unit having a pendent ultraviolet absorbing group. These oligomers are generally highly compatible with pressure sensitive adhesives and do not migrate out of the adhesive. Compositions comprising pressure sensitive adhesives and oligomers provide protection from ultraviolet light and have good transparency to visible and infrared light. Even after accelerated UV exposure and exposure to high temperature and high humidity conditions, these properties are typically kept good.

In one aspect, the present invention provides a composition comprising a blend of a pressure sensitive adhesive and an ultraviolet light-absorbing oligomer. The ultraviolet-absorbing oligomer comprises a first divalent unit having a pendant ultraviolet absorber and a second divalent unit represented by the formula:

Wherein R ¹ is hydrogen or methyl and R ² is alkyl having 4 to 22 carbon atoms. In some embodiments, the pressure sensitive adhesive is an acrylic pressure sensitive adhesive comprising a second 2-unit unit, and for at least some of the second 2-unit units in the pressure sensitive adhesive, R ² is a second 2-unit unit in ultraviolet- ≪ / RTI > is alkyl having the same number of carbon atoms as at least some of the < RTI ID = 0.0 &

The composition may be useful, for example, for bonding a film to the surface of an article or for bonding any two surfaces together. Thus, in another aspect, the invention provides an article comprising the composition. The article is, for example, a photovoltaic device or film in which the composition is disposed on at least a portion of the surface. The film may be, for example, a vehicle wrap, a graphic film, a construction film, a window film, or a barrier film.

In another aspect, the invention provides an assembly comprising a first polymeric film substrate having a first surface and a second surface opposite to the first surface, a second polymeric film substrate disposed on the first surface of the first polymeric film A pressure sensitive adhesive layer having a first surface and a second surface opposite the first surface, wherein the first surface of the pressure sensitive adhesive is disposed on the barrier film opposite the first polymer film substrate, And a second polymeric film substrate disposed on a second surface of the pressure sensitive adhesive layer. The pressure-sensitive adhesive layer comprises an ultraviolet-absorbing oligomer having a first divalent unit having a pendant ultraviolet absorber and a second dunner unit represented by the formula:

Wherein R ¹ is hydrogen or methyl and R ² is alkyl having 4 to 22 carbon atoms.

The UVA in the pressure sensitive adhesive (PSA) is useful for protecting the PSA and the underlying film or structure from UV light. In the case of conventional UVA, not only migration out of the adhesive layer but also aggregation and resulting optical defects can be a problem. The ultraviolet light-absorbing oligomers disclosed herein have superior compatibility in PSA formulations as compared to the same class of commercially available UVAs, as evidenced by the transparency and transmittance of PSA. Furthermore, in some embodiments, the second divalent units and optionally the third divalent units in the ultraviolet light-absorbing oligomer described herein are the same as those in the PSA formulations. Increased compatibility, as evidenced by the transparency and transmittance data, is observed in these embodiments, as compared to oligomers that are mostly derived from methyl methacrylate.

In this application:

Terms such as "a", "an", and "the" are not intended to refer only to singular entities, The terms indefinite article and definite article are used interchangeably with the term "at least one ".

Including at least one of the following phrases "includes any one of the items in the list and any combination of two or more items in the list. The phrase "at least one of" after the list refers to any one of the items in the list or any combination of two or more items in the list.

The term " ultraviolet absorber "or ultraviolet light absorber refers to a covalently attached ultraviolet absorber (UVA). It is well known to those skilled in the art that UVA can dissipate heat energy absorbed from UV radiation as heat by reversible intramolecular proton transfer. UVA is selected such that the oligomer in any embodiment of the oligomer or second oligomer described herein absorbs 70%, 80%, or 90% or more of the incident light in the wavelength range of 180 nanometers (nm) to 400 nm do.

"Alkyl group" and the prefix "alk-" include both straight chain and branched chain and cyclic groups. Unless otherwise specified, alkyl groups herein have up to 20 carbon atoms. The cyclic group may be monocyclic or polycyclic and, in some embodiments, may have from 3 to 10 ring carbon atoms.

For example, with respect to alkyl (which may or may not be fluorinated), alkylene, or arylalkylene, the phrase "at least one -O-group intervened"Quot; refers to having a portion of an alkyl, alkylene, or arylalkylene. For example, -CH ₂ CH ₂ -O-CH ₂ -CH ₂ - is an alkylene group interposed with -O-.

The term "polymer" refers to a molecule that has a structure that essentially comprises multiple repeats of a unit derived from a molecule of low relative molecular mass, in fact or conceptually. The term "polymer" encompasses oligomers.

All numerical ranges include non-integer values between its endpoints and endpoints (e.g., 1 to 5 include 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.) box).

Ultraviolet light-absorbing oligomers useful in compositions according to the present invention are linear or branched. Typically, the ultraviolet light-absorbing oligomer is a linear oligomer. The ultraviolet light-absorbing oligomer may be a random copolymer or a block copolymer. The ultraviolet-absorbing oligomer is not covalently crosslinked. Thus, in contrast to covalently crosslinked polymers that are not soluble in solvents and are nearing infinity in molecular weight, ultraviolet-absorbing oligomers can be dissolved in solvents and have measurable molecular weights. In some embodiments, the oligomer can be considered to be thermoplastic. Typically, the thermoplastic material is melt-processable, for example, by an extrusion process. Oligomers useful in compositions according to the present invention have a number average molecular weight of up to 150,000 grams / mole. In some of these embodiments, the oligomer has a number average molecular weight of up to 120,000, 100,000, 90,000, 80,000, 70,000, 60,000, 50,000, 40,000, 30,000, 20,000 grams / mole, or 20,000 grams / , Or 18,500 grams / mole). In some embodiments, the number average molecular weight of the oligomer may be greater than 1000 grams / mole, greater than 5,000 grams / mole, or greater than 7,500 grams / mole. Useful ultraviolet light-absorbing oligomers typically have a molecular weight and composition of a predetermined distribution. The weight average molecular weight and the number average molecular weight can be measured, for example, by gel permeation chromatography (i.e., size exclusion chromatography) using techniques known to those skilled in the art.

Ultraviolet light-absorbing oligomers useful in compositions according to the present invention include first divalent units comprising a pendant ultraviolet absorption (UVA) group in any of its embodiments. Any class of UVA may be useful to provide UVA groups. Examples of useful classes include benzophenone, benzotriazole, triazine, cinnamate, cyanoacrylate, dicyanoethylene, salicylate, oxanilide, and para-aminobenzoate. In some of these embodiments, the pendant ultraviolet absorber comprises triazine, benzophenone, or benzotriazole. In some embodiments of the composition according to the present invention, the pendant ultraviolet absorber is triazine. In some embodiments, the pendant ultraviolet absorber has an enhanced spectral coverage range in the long wave UV region (e.g., 315 nm to 400 nm), thereby blocking high wavelength UV light that can cause yellowing in the polymer. The first two-valent unit can be regarded as a repeating unit in the ultraviolet absorbing oligomer.

In some embodiments of the composition or method according to the present invention, the first 2-unit is represented by the formula - [CH ₂ -C (H) UVA -] -, - [CH ₂ -C (H) C OX-UVA -] -, - [- CH 2 -C (H) C (O) -NH-X-UVA -] -, - [- CH 2 -C (CH 3) C (O) -OX-UVA -] -, or - [CH ₂ -C (CH ₃ ) C (O) -NH-X-UVA -] -, wherein X is a bond or 1 to 10 In embodiments from 2 to 6 or from 2 to 4) carbon atoms optionally substituted with one or more -O- groups and optionally substituted by hydroxyl groups, UVA is an alkylene or alkylene group substituted with a UVA group Mentioned embodiment of the present invention. In the alkyleneoxy group, oxygen is attached to the UVA group. Oligomers may be independently selected (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 15 or more, or 20 or more up to 30, 35, 40, 45, 50, , Or up to 500 or more) repeating units. The repeat unit may be derived from a substituted vinyl, substituted acrylate, or substituted methacrylate group. In some of these embodiments, each first 2-membered unit is independently represented by the formula:

Wherein, R ¹ is hydrogen or methyl, V is O or NH, X is a bond or X has carbon atoms of from 1 to 10 (in some embodiments, 2 to 6 or 2 to 4), optionally Is an alkylene or alkyleneoxy group optionally interrupted by one or more -O- groups and optionally substituted by a hydroxyl group, R is alkyl (e.g. having 1 to 4 carbon atoms), n is 0 or 1, Z is a benzoyl group, a 4,6-bisphenyl [1,3,5] triazin-2-yl group, or a 2H-benzotriazol-2-yl group, wherein the benzoyl group, 4,6- The [1,3,5] triazin-2-yl group and the 2H-benzotriazol-2-yl group may optionally be substituted by one or more alkyl, aryl, alkoxy, hydroxyl, or halogen substituents, . In some embodiments, the alkyl and / or alkoxy substituents independently have from 1 to 4 or from 1 to 2 carbon atoms. In some embodiments, each halogen substituent is independently chloro, bromo, or iodo. In some embodiments, each halogen substituent is a chloro group. The term "aryl ", as used herein, refers to a carbocyclic ring containing one, two, or three rings and optionally containing at least one heteroatom (e.g., O, S, or N) Aromatic rings or ring systems. Examples of aryl groups include phenyl, naphthyl, biphenyl, fluorenyl, as well as furyl, thienyl, pyridyl, quinolinyl, isoquinolinyl, indolyl, isoindolyl, triazolyl, pyrrolyl, Tetrazolyl, imidazolyl, pyrazolyl, oxazolyl and thiazolyl. In the alkyleneoxy group, oxygen is attached to the substituted benzene ring. In some embodiments, each V is O and X is ethylene, propylene, butylene, ethyleneoxy, propyleneoxy, or butyleneoxy, with oxygen attached to the substituted benzene ring. In some embodiments, n is zero. In some embodiments, R is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s-butyl or t-butyl and n is 1. In some embodiments, Z is an unsubstituted benzoyl group. In some embodiments, Z is 4,6-bis (2,4-dimethylphenyl) [1,3,5] triazin-2-yl; 4,6-bis (2,4-diethylphenyl) [1,3,5] triazin-2-yl; 4,6-bis (2,4-dimethoxyphenyl) [1,3,5] triazin-2-yl; Or 4,6-bis (2,4-diethoxyphenyl) [1,3,5] triazin-2-yl. In some embodiments, Z is 2H-benzotriazol-2-yl or 5-chloro-2H-benzotriazol-2-yl. In some embodiments, Z is 4,6-bisphenyl [1,3,5] triazin-2-yl. In some embodiments, at least some of the first divalent units in the ultraviolet light-absorbing oligomer comprise different Z groups.

In embodiments of the compositions disclosed herein wherein the ultraviolet light-absorbing group is triazine, at least some of the first 2-valent units may be represented by the formula:

Wherein R, R, R ^1, X, and V are as described above in any of their embodiments, each Ar is optionally one or more alkyl, aryl, alkoxy, hydroxyl, or halogen substituents, or of these substituents ≪ / RTI > In some embodiments, the alkyl and / or alkoxy substituents independently have from 1 to 4 or from 1 to 2 carbon atoms. In some embodiments, each halogen substituent is independently chloro, bromo, or iodo. In some embodiments, each halogen substituent is a chloro group. Aryl substituents are as defined above. In some embodiments, Ar is 2,4-dimethylphenyl; 2,4-diethylphenyl; 2,4-dimethoxyphenyl; Or 2,4-diethoxyphenyl.

In embodiments of the compositions disclosed herein wherein the ultraviolet light-absorbing group is triazine, at least some of the first 2-valent units may be represented by the formula:

Wherein R ¹ , X, and V are as described above in any of their embodiments.

Ultraviolet light-absorbing oligomers useful in the compositions according to the present invention include at least one (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 15 or more At least 20, at most 30, 35, 40, 45, 50, 100, 200, 500, 1000, or at most 1500 or more)

(In some embodiments, the hydrogen, in some embodiments, methyl), wherein each R ¹ is independently hydrogen or methyl, each R ² is independently alkyl having 1 to 22 carbon atoms (in the form of some embodiments Lt; / RTI > In some embodiments, each R < ² > in the second divalent unit is independently selected from the group consisting of 4 to 22, 4 to 20, 4 to 18, 4 to 16, 4 to 12, or 6 to 12 carbon ≪ / RTI > In some of these embodiments, R ² has 8 carbon atoms (e.g., R ² is ethylhexyl or iso-octyl).

In some embodiments, the ultraviolet light-absorbing oligomer useful in the composition according to the present invention comprises at least one (e.g., 2, 3, 4, 5, 6, 5, 6, 7, 8, 9, 10, 15 or more, or 20 or more, 30, 35, 40, 45, 50, 100, 200, 500 or more than 1000). The aminocarbonyl group is aminocarbonyl _{(-C (O) -NH 2)} , alkylamino-carbonyl, dialkyl amino carbonyl may imidazol, wherein alkyl aminocarbonyl or alkyl in dialkylamino carbonyl is hydroxyl ≪ / RTI > It will be understood by those skilled in the art that an aminocarbonyl group is also known as an amido group. If there are more than one third 2-unit units, then the third 2-unit units can be selected independently.

Oligomers according to the present invention can be prepared, for example, by polymerizing a mixture of components, typically in the presence of an initiator. The term "polymerization" means to form a polymer or oligomer comprising at least one identifiable structural element attributable to each component. Typically, the step of preparing an ultraviolet light-absorbing oligomer comprises combining components comprising at least a first monomer having an ultraviolet light-absorbing group, a second monomer, and optionally at least one third monomer as described below .

Suitable first monomers for some embodiments of the compositions disclosed herein include benzophenone, benzotriazole, triazine, cinnamate, cyanoacrylate, dicyanoethylene, salicylate, oxanilide, or para- Aminobenzoate groups. Examples of suitable first monomers include 2- (cyano-?,? - biphenylacryloyloxy) ethyl-1-methacrylate, 2- (? -Cyano-?,? -Biphenylacryloyloxy (2-ethylphenyl) oxamide, vinyl-4-ethyl- alpha -cyano-beta-phenyl cinnamate, N- Hydroxy-4- (2-hydroxy-3-methacryloyloxypropoxy) benzophenone, 2-hydroxy-4-methacryloyloxybenzophenone, 2- (4-acryloyloxybutoxy) benzophenone, 2,2'-dihydroxy-4- (2-acryloyloxyethoxy) benzophenone, ) Benzophenone, 4- (2-acryloyloxyethoxy) -4'- (2-hydroxyethoxy) benzophenone, 4- (allyloxy) -2-hydroxybenzophenone, 2-benzotriazole, 2- (2'-hydroxy-3'-methacrylamidomethyl-5'-octylphenyl) benzotriazole, 2- (2H Methyl-6- (2-propenyl) phenol, 2- (2'-hydroxy-5'-methacryloyloxyethylphenyl) -2H-benzotriazole , 2 - (2'-hydroxy-5'-methacryloyloxyethylphenyl) -5-chloro-2H-benzotriazole, 2- Benzotriazole, 2- (2'-hydroxy-5'-methacryloyloxypropylphenyl) -5-chloro-2H-benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methacryloyloxyethylphenyl) -2H-benzotriazole, Benzothiazole, 2,4-diphenyl-6- [2-hydroxy-4- (2-acryloyloxyethoxy)] - 1,3,5-triazine, Bis (2-methylphenyl) -6- [2-hydroxy-4- (2- acryloyloxyethoxy)] - 1,3,5-triazine, 2,4- Methoxyphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)] - 1,3,5-triazine, 2,4- (2-ethylphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)] - 1,3,5-triazine, 2,4- 4- (2-acryloyloxyethoxy)] - 1,3,5-triazine, 2,4-diphenyl-6- [ 2-methacryloyloxyethoxy)] - 1,3,5-triazine, 2,4-bis (2-methylphenyl) -6- [ Methoxyphenyl) -6- [2-hydroxy-4- (2-methacryloyloxyethoxy)] - 1,3,5-triazine, 1,3,5-triazin, 2,4-bis (2-ethylphenyl) -6- [2-hydroxy-4- (2- methacryloyloxyethoxy)] - 2-methoxyphenyl) -6-f2-hydroxy-4- (2-methacryloyloxyethoxy)] - 1,3,5-triazine, 2, (2,4-dimethoxyphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)] - 1,3,5-triazine, 2,4-bis (2,4-dimethylphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)] - 1,3,5-tria (2,4-diethoxyphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)] - 1,3,5-triazine, 2 , 2,4-diethylphenyl) -6- [2-hydroxy-4- (2-acryloyloxyethoxy)] - 1,3,5-triazine, Methacrylate and acrylates of the methacrylates described above. The combination of these first monomers can be used to prepare oligomers. In some embodiments, the first monomer comprises a triazine, benzophenone, or benzotriazole group. In these embodiments, the first monomer may be any monomer including the triazine, benzophenone, or benzotriazole group listed above. In some embodiments of the composition according to the present invention, the first monomer comprises a triazine group. In these embodiments, the first monomer may be any monomer including the triazine group listed above.

Many of these first monomers are commercially available from various chemical sources. Others include UVA with an available hydroxyl group (e.g., other than a phenolic hydroxyl group in the ortho position to a triazine, benzoyl, or benzotriazolyl group) with (meth) acrylamide using conventional esterification methods, Acrylic acid or its equivalent. The term (meth) acrylate refers to both acrylic and methacrylic. In the case of UVA having an available phenolic group (e.g., other than a phenolic hydroxyl group in the ortho position to the triazine, benzoyl, or benzotriazole group), the phenol group is treated with ethylene carbonate or ethylene oxide to form the hydro- Hydroxyethyl group, which can then be treated with (meth) acrylic acid or its equivalent using conventional esterification methods.

Ingredients useful for making the oligomers disclosed herein include a second monomer. In some of these embodiments, the oligomer is prepared by including in the component to be polymerized at least one compound represented by the formula R ² -OC (O) -C (R ¹ ) = CH ₂ as the second monomer. R ¹ and R ² are as defined above in any of their embodiments. Suitable second monomers of this formula are selected from the group consisting of butylacrylate, isoamyl acrylate, ethylhexyl acrylate, isooctyl acrylate, nonyl acrylate, dodecyl acrylate, hexadecyl methacrylate, octadecyl methacrylate, Aryl acrylates, behenyl methacrylates, acrylates of the above-mentioned methacrylates, and methacrylates of the above-mentioned acrylates. Many of these second monomers are commercially available from, for example, several chemical suppliers (e.g., Sigma-Aldrich Company of Milwaukee, Wis .; VWR International of West Chester, Pennsylvania, USA) ; Monomer-Polymer & Dajac Labs, Pisverville, Pa.; Avocado Organics, Ward Hill, Mass., USA; and Ciba Specialty Chemicals, Ciba Specialty Chemicals) or may be synthesized by conventional methods. Some of these second monomers are available as single isomers (e.g., straight chain isomers) of a single compound. Others are available, for example, as mixtures of isomers (e.g., straight chain isomers and branched isomers), mixtures of compounds (e.g., hexadecyl acrylate and octadecyl acrylate), and combinations thereof.

Suitable third monomers in some embodiments of the oligomers disclosed herein include acrylic acid (e.g., acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid), (meth) acrylamides (e.g., N-ethyl acrylamide, N-hydroxyethyl acrylamide, N-octylacrylamide, Nt-butyl acrylamide, N, N-dimethylacrylamide, Dihydroxyethyl acrylamide, and methacrylamides of the foregoing acrylamides), hydroxyalkyl (meth) acrylates (e.g., 2-hydroxyethyl acrylate or methacrylate, 3-hydroxypropyl acrylate or meth Acrylate, 4-hydroxybutyl acrylate or methacrylate, 8-hydroxyoctyl acrylate or methacrylate, or 9-hydroxynonylarc It includes acrylate or methacrylate). N-vinylpyrrolidone and N-vinylcaprolactam may also be useful in the preparation of the ultraviolet light-absorbing oligomer described herein.

In some embodiments, ultraviolet-absorbing oligomers useful in compositions according to the present invention and / or in accordance with the present invention are represented by the following formula:

.

.

Where x, v, z, n, R, R ¹ , and R ² are as defined above in any of their embodiments and y and z are any of the ranges described above in any of their embodiments . It is to be understood that the order of presentation of the binary units in this formula is merely for convenience and is not intended to specify that the oligomer is a block copolymer. Random copolymers having first and second divalent units are also included in the indication. This indication may also include any third unit described above in any order.

The polymerization reaction for preparing the oligomers useful in the composition according to the invention can be carried out in the presence of an added free radical initiator. Free radical initiators such as those well known and used in the art can be used to initiate polymerization of the components. Examples of suitable free radical initiators include azo compounds such as 2,2'-azobisisobutyronitrile (AIBN), 2,2'-azobis (2-methylbutyronitrile), or azo-2-cyano Tert -butyl or tert -amyl hydroperoxide), dialkyl peroxides (e.g., di- tert -butyl or dicumyl peroxide), peroxyesters (such as tert -Butyl perbenzoate or di- tert -butyl peroxyphthalate), and diacyl peroxide (e.g., benzoyl peroxide or lauryl peroxide).

The free radical initiator may also be a photoinitiator. Examples of useful photoinitiators include benzoin ethers (e.g., benzoin methyl ether or benzoin butyl ether); Acetophenone derivatives (e.g., 2,2-dimethoxy-2-phenylacetophenone or 2,2-diethoxyacetophenone); 1-hydroxycyclohexyl phenyl ketone; And acylphosphine oxide derivatives and acylphosphonate derivatives such as bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, diphenyl-2,4,6-trimethylbenzoylphosphine oxide, Phenyl phenyl-2,4,6-trimethylbenzoylphosphine oxide, or dimethyl pivaloylphosphonate). A number of photoinitiators are available, for example, under the trade designation "IRGACURE" from BASF, Floham Park, NJ, USA. The photoinitiator may be selected such that the wavelength of light required to initiate polymerization is not absorbed by the ultraviolet absorber.

In some embodiments, the polymerization reaction is carried out in a solvent. The components may be present in the reaction medium at any suitable concentration (e.g., from about 5% to about 80% by weight based on the total weight of the reaction mixture). Illustrative examples of suitable solvents include aliphatic and alicyclic hydrocarbons such as hexane, heptane, cyclohexane, aromatic solvents such as benzene, toluene, xylene, ethers such as diethyl ether, , And diisopropyl ether), esters (e.g., ethyl acetate and butyl acetate), alcohols such as ethanol and isopropyl alcohol, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, (E.g., methyl chloroform, 1,1,2-trichloro-1,2,2-trifluoroethane, trichlorethylene, trifluoro toluene, and 3M Company, 3M Company, St. Paul, MN, Company, under the trade names "HFE-7100" and "HFE-7200 "), and mixtures thereof.

The polymerization can be carried out at any temperature suitable for carrying out the organic free radical reaction. The temperatures and solvents for a particular application may be selected by those skilled in the art based on considerations such as the solubility of the reagents, the temperature required for the use of the particular initiator, and the desired molecular weight. While it is not practical to enumerate specific temperatures suitable for all initiators and all solvents, a suitable temperature is generally from about 30 캜 to about 200 캜 (in some embodiments, from about 40 캜 to about 100 캜, or from about 50 캜 to about 80 Lt; 0 > C).

The free radical polymerization can be carried out in the presence of a chain transfer agent. Typical chain transfer agents that can be used in the preparation of the compositions according to the present invention include hydroxyl-substituted mercaptans (e.g., 2-mercaptoethanol, 3-mercapto-2-butanol, 3-mercapto- 3-mercapto-1-propanol, and 3-mercapto-1,2-propanediol (i.e., thioglycerol)); Poly (ethylene glycol) -substituted mercaptans; Carboxy-substituted mercaptans (e.g., mercaptopropionic acid or mercaptoacetic acid): amino-substituted mercaptans (e.g., 2-mercaptoethylamine); Bifunctional mercaptans such as di (2-mercaptoethyl) sulfide; And aliphatic mercaptans (e.g., octyl mercaptan, dodecyl mercaptan, and octadecyl mercaptan).

Using techniques known in the art, for example, the concentration and activity of the initiator, the concentration of each reactive monomer, the temperature, the concentration of the chain transfer agent, and the solvent can be adjusted to control the molecular weight of the oligomer.

The weight ratios of the first, second, and third dendrimer units in the oligomers disclosed herein may vary in any of their embodiments. For example, the first divalent unit may be present in the range of from 5 to 50% (in some embodiments, from 10 to 40% or from 10 to 30%) based on the total weight of oligomers in the ultraviolet-absorbing oligomer. The second divalent unit may be present in the range of 5 to 95% based on the total weight of the oligomer. In some embodiments, the second divalent unit is present in the oligomer in an amount of up to 90, 80, 75, or 70 weight percent based on the total weight of the oligomer. The third divalent unit may be present in the range of 1 to 15, 1 to 10, or 1 to 5 weight percent based on the total weight of the oligomer. Or ultraviolet light-absorbing oligomers may not be present in the third binar unit. In some embodiments, the oligomer may comprise at least one (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, or more than 20, up to 30, 35, 40, 45, (E.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, At least 15, or at least 20, at most 30, 35, 40, 45, 50, 100, 200, or at most 500 or more) independently selected first 2 units.

The composition according to the present invention comprises a blend of a pressure sensitive adhesive and ultraviolet light-absorbing oligomer (s). By "blend" it is to be understood that the pressure sensitive adhesive and the ultraviolet light-absorbing oligomer (s) are separate components. They are generally not covalently bonded to each other. Ultraviolet light-absorbing monomers grafted onto PSA do not constitute a blend of PSA and oligomer (s) as disclosed herein.

Ultraviolet light-absorbing oligomer In any embodiment of the ultraviolet light-absorbing oligomer, the ultraviolet light-absorbing oligomer as described above is incorporated into the pressure sensitive adhesive composition. PSA is well known to those of skill in the art having properties including (1) strong and permanent tack, (2) adhesion at a pressure below the finger pressure, (3) sufficient retention on the adherend, and ) Sufficient cohesive strength to be able to be cleanly removed from the adherend. Materials that have been found to function well as PSAs are polymers that are engineered and formulated to exhibit the requisite viscoelastic properties that bring about the desired balance of tack, peel adhesion, and shear holding power.

One useful method for identifying pressure sensitive adhesives is the Dahlquist standard. This standard is based on the assumption that a pressure sensitive adhesive is applied to the surface of a substrate by the method described in Handbook of Pressure Sensitive Adhesive Technology, Donatas Satas (Ed.), 2nd Edition, p. 172, Van Nostrand Reinhold, New York , NY, 1989] is defined as an adhesive having a 1 × 10 ^-6 ㎠ / 1 cho creep compliance of greater than dyne (creep compliance), as described in. Alternatively, the modulus can be defined as an adhesive having a storage modulus of less than about 1 x 10 < ⁶ > / cm < 2 >, since the primary approximation is the reciprocal of creep compliance.

Examples of useful classes of PSAs that can comprise ultraviolet light-absorbing oligomers according to the present invention include acrylic, silicone, polyisobutylene, urea, natural rubber, synthetic rubbers such as styrene or substituted styrene as A block, , ABA tri-block copolymers of polybutadiene, hydrogenated polybutadiene, polyisoprene, hydrogenated polyisoprene, or a combination thereof, and combinations of these classes. Some useful commercially available PSAs in which the ultraviolet light-absorbing oligomer according to the present invention can be incorporated include UV curable PSAs such as those commercially available from Adhesive Research, Inc. of Glen Lock, Pa. Available under the trade designations " ARCLEAR 90453 "and" ARCLEAR 90537 ", and those commercially available from 3M Company of St. Paul, Minn., USA under the trademark "optically transparent laminating adhesive CLEAR LAMINATING ADHESIVE 8171 ", "optically transparent laminating adhesive 8172 ", and" optically transparent laminating adhesive 8172P ".

In some embodiments, the PSA composition in which the ultraviolet light-absorbing oligomer according to the present invention can be incorporated does not flow and is sufficient to provide slow or minimal penetration of oxygen and moisture through the adhesive bond line Barrier property. In addition, the PSA composition is substantially transparent to visible light and infrared light, so that it does not interfere with transmission of visible light through, for example, a window film, or absorption of visible light, for example, by a photovoltaic cell. PSA may have an average transmittance of at least about 75% (in some embodiments, at least about 80, 85, 90, 92, 95, 97, or 98%) over the visible portion of the spectrum measured along the vertical axis. In some embodiments, the PSA has an average transmittance of greater than or equal to about 75% (in some embodiments, about 80, 85, 90, 92, 95, 97, or 98% Or more).

In some embodiments, useful PSA compositions disclosed herein have a modulus of elasticity (tensile modulus) of at most 50,000 psi (3.4 x 10 ⁸ Pa). The tensile modulus can be measured, for example, by tensile test equipment, such as a test system available under the trade designation "INSTRON 5900 " from Instron, Norwood, Mass. In some embodiments, the tensile modulus of PSA is at most 40,000, 30,000, 20,000, or 10,000 psi (2.8 x 10 ⁸ Pa, 2.1 x 10 ⁸ Pa, 1.4 x 10 ⁸ Pa, or 6.9 x 10 ⁸ Pa).

In some embodiments, the PSA composition comprising an ultraviolet light-absorbing oligomer according to the present invention is an acrylic PSA. As used herein, the term "acrylic" or "acrylate" includes compounds having at least one of acrylic or methacrylic groups. Useful acrylic PSAs can be prepared, for example, by combining two or more different monomers (second and third monomers as described above). Examples of suitable second monomers include 2-methylbutyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, lauryl acrylate, n-decyl acrylate, 4-methyl- Acrylate, sec-butyl acrylate, isononyl acrylate, and methacrylates of the abovementioned acrylates. Examples of suitable third monomers include (meth) acrylic acid (e.g., acrylic acid, methacrylic acid, itaconic acid, maleic acid, and fumaric acid), (meth) acrylamides (such as acrylamide, methacrylamide, , N-hydroxyethylacrylamide, N-octylacrylamide, Nt-butyl acrylamide, N, N-dimethylacrylamide, N, N-diethylacrylamide, Amide, and methacrylamides of the foregoing acrylamides), (meth) acrylates (such as 2-hydroxyethyl acrylate or methacrylate, cyclohexyl acrylate, t-butyl acrylate, isobornyl acrylate, And methacrylates of the abovementioned acrylates), N-vinylpyrrolidone, N-vinylcaprolactam, alpha-olefins, vinyl ethers, allyl ethers, styrenic monomers, or maleates.

In some embodiments, the pressure sensitive adhesive is an acrylic pressure sensitive adhesive comprising a second 2-unit unit, and for at least some of the second 2-unit units in the pressure sensitive adhesive, R ² is a second 2-unit unit in ultraviolet- ≪ / RTI > is alkyl having the same number of carbon atoms as at least some of the < RTI ID = 0.0 & For example, for one to isooctyl acrylate PSA to a substrate, this is, that the ² 2 R 2 is an alkyl having 8 carbon atoms ultraviolet light comprising units - may also be useful for absorbing oligomer. By matching the R ² groups in the second 2-unit of ultraviolet-absorbing oligomer with PSA, it is possible to improve the compatibility between the PSA and the oligomer, resulting in higher light transmittance and transparency in the PSA composition. Methylmethacrylate copolymers with the first monomers described above to prepare oligomers for incorporation into PSA (see JP2000123621, published April 28, 2000), the present inventors have found that such Type oligomers resulted in lower transparency in the PSA composition than in the case where the ultraviolet light-absorbing oligomer comprises divalent units consistent with the divalent units in the PSA (in the following, Table 1 ). If both the pressure-sensitive adhesive and the ultraviolet-absorbing oligomer comprise the same third divalent unit (made from the same third monomer as described above), further compatibility improvement can be achieved.

Acrylic PSA can also be prepared by including a crosslinking agent in the formulation. Exemplary cross-linking agents include copolymerized, multifunctional ethylenically unsaturated monomers such as 1,6-hexanediol diacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, and 1,2-ethylene glycol di Acrylate); Acylated benzophenones, such as those described in U.S. Patent No. 4,737,559 (Kellen et al.), Which is an excipient capable of hydrogenation, are available from Satomer Company, Exton, Pa. (Benzoyl-p-phenylene) -N '- (methacryloxy methylene) -carbamoyloxybenzophenone, p- ) -Carbodiimide, and monomers described in U.S. Patent No. 5,073,611 (Rehmer et al.), Including p-acryloxy-benzophenone; For example, in the third monomer described above, a nonionic crosslinking agent (e.g., 1,4-bis (ethyleneiminocarbonylamino) benzene), which is essentially free of olefinic unsaturation and capable of reacting with a carboxylic acid group, (Ethyleneiminocarbonylamino) diphenylmethane, 1,8-bis (ethyleneiminocarbonylamino) octane, 1,4-tolylene diisocyanate, 1,6-hexamethylene diisocyanate, N , N'-bis-1,2-propylene isophthalamide, diepoxide, dianhydride, bis (amide), and bis (imide); (Tri-chloromethyl) -6- (2, 3-di-tert-butoxycarbonylamino) propionic acid, which is essentially non-conjugated with the first and second monomers, 4-methoxy) phenyl) -s-triazine; 2,4-bis (trichloromethyl) -6- (3,4-dimethoxy) phenyl) -s-triazine; 2,4-bis (trichloromethyl) -6- (3,4,5-trimethoxy) phenyl) -s-triazine; 2,4-bis (trichloromethyl) -6- (2,4-dimethoxy) phenyl) -s-triazine; Bis (trichloromethyl) -6- (3-methoxy) phenyl) -s-triazine as described in U.S. Patent No. 4,330,590 (Vesley); Bis (trichloromethyl) -6- (4-methoxy) naphthenyl-s-triazine and 2,4-bis (trichloromethyl) benzene as described in U.S. Patent No. 4,329,384 (Beesley) 6-naphthenyl-s-triazine).

Typically, the second monomer is used in an amount of 80 to 100 parts by weight (pbw) based on 100 parts by weight of the total weight of the copolymer, and the third monomer is used in an amount of 0 to 20 pbw based on 100 parts by weight of the total weight of the copolymer do. The crosslinking agent may be used in an amount of from 0.005 to 2% by weight, for example from about 0.01 to about 0.5% by weight or from about 0.05 to 0.15% by weight, based on the total weight of the monomers.

Acrylic PSAs useful in the practice of the present invention may be prepared by methods known in the art, for example, using heat (e.g., using heat, electron beam radiation, or ultraviolet radiation), for example, in a solvent or by solventless, bulk, free radical polymerization processes . Such polymerization is typically facilitated by polymerization initiators (e.g., photoinitiators or thermal initiators). Examples of suitable polymerization initiators include those described above for the preparation of ultraviolet light-absorbing oligomers. The polymerization initiator is used in an amount effective to promote polymerization of the monomer (for example, 0.1 part by weight to 5.0 parts by weight or 0.2 parts by weight to 1.0 part by weight based on 100 parts by total monomer content).

When a photo-crosslinking agent is used, the coated adhesive may be exposed to ultraviolet radiation having a wavelength of from about 250 nm to about 400 nm. The radiant energy required to crosslink the adhesive in this wavelength range is from about 100 milliwatts / cm2 to about 1,500 milliwatts / cm2, or, more specifically, from about 200 milliwatts / cm2 to about 800 milliwatts / cm2.

A useful solventless polymerization process is disclosed in U.S. Patent No. 4,379,201 (Heilmann et al.). Initially, a portion of the photoinitiator is used to expose the mixture of the second and third monomers to UV radiation for a period of time sufficient to form a coatable base syrup in an inert environment, followed by addition of the crosslinking agent and the remaining photoinitiator, Can be polymerized. (Which may be, for example, a Brookfield viscosity of about 100 centipoise to about 6000 centipoise at 23 DEG C when measured at 60 rpm, using a No. 4 LTV spindle) This final syrup can be coated onto a substrate, for example, a polymer film substrate. Once the syrup is coated onto a substrate, such as a polymer film substrate, additional polymerization and cross-linking can be performed in an inert environment (e.g., oxygen-free, nitrogen, carbon dioxide, helium, and argon). A sufficiently inert atmosphere can be achieved by covering the layer of photoactive syrup with a polymer film that is transparent to UV radiation or e-beam, for example a silicon-treated PET film, and irradiating the film through air.

PSAs generally include high molecular weight polymers. In some embodiments, the acrylic polymer of the pressure sensitive adhesive in the composition according to the present invention has a number average molecular weight of at least 300,000 grams / mole. A number average molecular weight of less than 300,000 grams / mole can produce a PSA with low durability. In some embodiments, the number average molecular weight of the PSA ranges from 300,000 to 3 million, from 400,000 to 2 million, from 500,000 to 2 million, or from 300,000 to 1 million grams / mole. Therefore, in some embodiments, the number average molecular weight of the ultraviolet-absorbing oligomer is not more than 1/2 of the number average molecular weight of the pressure-sensitive adhesive. In some embodiments, the ultraviolet light-absorbing oligomer has a number average molecular weight of 1/3, 1/5, or 1/10 or less of the number average molecular weight of the pressure-sensitive adhesive.

It may be useful to have a mixture of ultraviolet light-absorbing oligomers in the composition according to the invention. In some embodiments, the composition comprises at least two different ultraviolet light-absorbing oligomers in the blend, wherein each ultraviolet light-absorbing oligomer is independently selected from the group consisting of a first divalent unit, a second divalent unit, 2 < / RTI > Each ultraviolet-absorbing oligomer may independently comprise triazine, benzophenone, or benzotriazole. Two different ultraviolet light-absorbing oligomers may be useful having two different types of pendant ultraviolet absorbers. In these embodiments, the first binomial unit in the ultraviolet light-absorbing oligomer and the different second ultraviolet light-absorbing oligomer comprises different Z groups. In any of these embodiments, the different second ultraviolet light-absorbing oligomers may have at least one (e.g., 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, Second, third, fourth, fifth, sixth, seventh, eighth, eighth, eighth, eighth, At least one (e.g., at least one, preferably at least one, at least two, or more than one) of the first, second, third, fourth, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15 or more, 20 or more, 30, 35, 40, 45, 50, 100, 200, 500, ) ≪ / RTI > The first, second, and third bidentate units may be as described in any of the embodiments described above for the ultraviolet-absorbing oligomer. In some cases, a mixture of two different ultraviolet light absorbing oligomers may be useful to improve compatibility.

Other stabilizers can be added to compositions according to the present invention to improve their resistance to UV light. Examples of these include hindered amine light stabilizers (HALS) and antioxidants. Some suitable HALS include tetramethylpiperidine groups wherein the nitrogen atom on the piperidine may be unsubstituted or substituted by alkyl or acyl. Suitable HALS include, but are not limited to, decaneic acid, bis (2,2,6,6-tetramethyl- 1- (octyloxy) -4-piperidinyl) ester, bis (2,2,6,6- Peridyl) sebacate, 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro (4,5) Bis (2,2,6,6-tetramethyl-4-hydroxypiperidine succinate), and bis (N-methyl-2,2,6,6-tetramethyl-4-piperidyl) sebacate . Suitable HALS include, for example, those available under the trade designation "CHIMASSORB" from BASF. Exemplary antioxidants include those available under the trade designations IRGAFOS 126, IRGANOX 1010, and ULTRANOX 626, available from BASF, Floham Park, NJ, USA. . These stabilizers, when present, may be included in the composition according to the invention in any effective amount, typically up to 5, 2, and 1% by weight, and typically 0.1, 0.2, or 0.3% . For example, in some compositions, calcite may also be a useful additive to protect against corrosion of processing equipment not made of corrosion resistant steel.

In some embodiments of the composition, or method of making the composition or film, the composition is essentially free of volatile organic solvents. Volatile organic solvents are typically ones that have a boiling point of at most 150 ° C at atmospheric pressure. Examples thereof include esters, ketones, and toluene. "Essentially absent volatile organic solvent" means that the volatile organic solvent is present in an amount of up to 2.5% by weight (in some embodiments up to 2, 1, 0.5, 0.1, 0.05, or 0.01% by weight) May be present in an amount (e.g., from a previous synthesis step, or in a commercially available monomer). Advantageously, the compositions and films disclosed herein can be prepared without expensive manufacturing steps to remove organic solvents.

The composition according to the present invention may contain an ultraviolet light-absorbing oligomer and optionally a second ultraviolet light-absorbing oligomer in a useful amount. For example, the ultraviolet-absorbing oligomer may be present in the composition at up to about 25 weight percent based on the total weight of the composition. Where two or more different ultraviolet-absorbing oligomers are present, two or more are present in the composition in an amount of up to 25% of the total weight based on the total weight of the composition. The useful amount of ultraviolet-absorbing oligomer (s) may range from 1 to 25, 2 to 20, 3 to 15, or 4 to 10 weight percent based on the total weight of the composition. A useful amount of ultraviolet absorber (i.e., active UVA) may range from 0.5 to 15, 0.5 to 10, 1 to 7.5, or 2 to 5 wt%, based on the total weight of the composition.

In some embodiments, the composition according to the present invention is transmissive to both visible and infrared light. As used herein, the term "transmissive to visible and infrared light" means that the average transmittance over the visible and infrared light portions of the spectrum, measured along the vertical axis, is at least about 75% 85, 90, 92, 95, 97, or 98% or more). In some embodiments, the composition has an average transmittance of at least about 75% (in some embodiments, about 80, 85, 90, 92, 95, 97, or 98% in some embodiments) ranging from 400 nm to 1400 nm, Or more).

The compositions according to the invention may be useful for a variety of outdoor applications. For example, the composition according to the present invention may be applied to various applications such as, for example, traffic signs or other signs, other graphic films, anti-grafitti films, automotive exterior, roofing or other architectural films, barrier films, May be useful as a PSA layer.

The composition according to the present invention is useful, for example, in photovoltaic devices. In some embodiments, the composition (e.g., in the form of a film in any embodiment) is disposed on, on, or around a photovoltaic cell. Accordingly, the present invention provides a photovoltaic device comprising the composition disclosed herein, wherein the composition is used as a PSA in a photovoltaic device. Photovoltaic devices include photovoltaic cells developed using a variety of materials, each having its own absorption spectrum that converts solar energy into electricity. Each type of semiconductor material has a characteristic band gap energy that causes it to absorb light most efficiently at a given wavelength of light, or more specifically, absorb electromagnetic radiation over a portion of the sunlight spectrum . The compositions according to the invention typically do not interfere with the absorption of visible and infrared light by, for example, photovoltaic cells. In some embodiments, the composition has an average transmittance of at least about 75% (in some embodiments, about 80, 85, 90, 92, 95, 97 (in some embodiments, , Or 98% or more). Examples of materials used to make solar cells and their solar absorption band-edge wavelengths include: crystalline silicon single junctions (about 400 nm to about 1150 nm), amorphous silicon single junctions (about 300 nm to about 1150 nm) 720 nm), ribbon silicon (about 350 nm to about 1150 nm), CIS (copper indium selenide) (about 400 nm to about 1300 nm), CIGS (copper indium gallium di-selenide) ), CdTe (about 400 nm to about 895 nm), and GaAs multiple junctions (about 350 nm to about 1750 nm). The shorter wavelength left absorption band boundary of such a semiconductor material is typically 300 nm to 400 nm. Organic photovoltaic cells may also be useful. Those skilled in the art understand that novel materials are being developed for more efficient solar cells with their own inherent longer wavelength absorption band-boundaries. In some embodiments, the photovoltaic device comprising the composition according to the present invention comprises a CIGS cell. In some embodiments, the photovoltaic device to which the assembly is applied comprises a flexible film substrate.

The composition according to the present invention can be used as a PSA in a barrier stack (see, for example, U.S. Patent Application Publication No. 2012/0227809 (Bharti et al.) And U.S. Patent Application Publication No. 2012/0003451 Weigel et al., Which is incorporated herein by reference).

In some embodiments, the present invention provides an assembly comprising a first polymeric film substrate having a first surface and a second surface opposite the first surface, a barrier disposed on a first surface of the first polymeric film, A pressure sensitive adhesive layer having a film, a first surface and a second surface opposite the first surface, wherein the first surface of the pressure sensitive adhesive is disposed on the barrier film opposite the first polymer film substrate, And a second polymeric film substrate disposed on a second surface of the adhesive layer. The pressure sensitive adhesive may be as described in any of the preceding embodiments and includes at least one ultraviolet light-absorbing oligomer as described in any of the preceding embodiments.

The term "barrier film" refers to a film that provides a barrier to at least one of oxygen or water. Typically, the barrier film is selected to have a specified level of oxygen and moisture permeability required depending on the application. In some embodiments, the barrier film produced according to the present invention and / or according to the method of the present invention has a water vapor transmission rate (WVTR) of less than about 0.005 g / m ² / day at 38 ° C and 100% relative humidity; In some embodiments, less than about 0.0005 g / m ² / day at 38 ° C and 100% relative humidity; In some embodiments, less than about 0.00005 g / m ² / day at 38 ° C and 100% relative humidity. In some embodiments, the barrier film has a WVTR of about 0.005, 0.0005, or about 0.005 g / m ² / day at 50 캜 and 100% relative humidity of less than about 0.05, 0.005, 0.0005, or 0.00005 g / And less than 0.00005 g / m ² / day. In some embodiments, the barrier film has an oxygen permeability of less than about 0.005 g / m ² / day at 23 ° C and 90% relative humidity; In some embodiments, less than about 0.0005 g / m ² / day at 23 ° C and 90% relative humidity; And in some embodiments, less than about 0.00005 g / m ² / day at 23 ° C and 90% relative humidity.

In some embodiments of the assemblies disclosed herein, the barrier film comprises at least a first and a second polymeric layer separated by an inorganic barrier layer. In some embodiments, an inorganic layer, which may be an oxide layer, may be applied over the second polymeric layer. In some embodiments, the barrier film comprises a plurality of alternating layers of a second polymeric layer and an oxide layer on the first polymeric layer. The oxide layer and the second polymer layer together form a "dyad ", and in some embodiments, the barrier film may comprise more than one die add. Each oxide layer and / or the second polymer layer in the multilayer barrier film comprising more than one die add may be the same or different. An optional inorganic layer, which may be an oxide layer, may be applied over a plurality of alternating layers or die inserts. In some embodiments, the inorganic layer comprises at least one of silicon aluminum oxide or indium tin oxide.

The first and second polymeric layers may comprise any polymer suitable for deposition into a thin film. In some embodiments, the first and second polymeric layers may be formed from oligomers comprising various precursors, e.g., acrylate or methacrylate monomers and / or acrylates or methacrylates. In some embodiments of the barrier films and methods disclosed herein, at least one of the first or second polymer layer precursor comprises a methacrylate or acrylate monomer. Examples of useful methacrylate and acrylate precursors include urethane acrylate, isobornyl acrylate, isobornyl methacrylate, dipentaerythritol pentaacrylate, epoxy acrylate, epoxy acrylate blended with styrene, di- Butylene glycol diacrylate, pentaacrylate ester, pentaerythritol tetraacrylate, pentaerythritol triacrylate, ethoxylated (3) trimethylolpropane tetraacrylate, diethylene glycol diacrylate, 1,3-butylene glycol diacrylate, Trimethylolpropane triacrylate, ethoxylated (3) trimethylolpropane triacrylate, alkoxylated trifunctional acrylate ester, dipropylene glycol diacrylate, neopentyl glycol diacrylate, ethoxylated (4) bisphenol A dimethacrylate Cyclohexanedimethanol diacrylate ester, isobornyl methacrylate, cyclic diacrylate and tris (2-hydroxyethyl) isocyanurate triacrylate, acrylates of the methacrylates described above, and the aforementioned Methacrylate of acrylate. Further examples of useful acrylate or methacrylate precursors include, but are not limited to, trimethylolpropane triacrylate, trimethylolpropane diacrylate, hexane diol diacrylate, ethoxyethyl acrylate, phenoxyethyl acrylate, cyano But are not limited to, ethyl (mono) acrylate, octadecyl acrylate, isodecyl acrylate, lauryl acrylate, beta-carboxyethyl acrylate, tetrahydroperfuryl acrylate, dinitrile acrylate, pentafluorophenyl acrylate, Acrylate, 2-phenoxyethyl acrylate, 2,2,2-trifluoromethyl acrylate, and methacrylates of any of these acrylates.

The first and second polymeric layers can be formed by applying a layer of monomer or oligomer to the substrate and subsequent to flash evaporation and deposition of, for example, spin-crosslinkable monomers, for example, an electron beam device, a UV light source, For example, by crosslinking the layer by cross-linking using a suitable solvent, an extruder, an electric discharge device, or other suitable device to form the polymer in situ. Coating efficiency can be improved by cooling the substrate.

The monomers or oligomers may also be applied to the substrate using conventional coating methods, such as roll coating (e.g., gravure roll coating), or spray coating (e.g., electrostatic spray coating), as described above , Followed by cross-linking. The first and second polymer layers may also be formed by applying a layer containing an oligomer or polymer in a solvent, and drying the applied layer so as to remove the solvent. Chemical vapor deposition (CVD) may also be used in some cases.

In some embodiments, at least one of the first or second polymeric layer comprises a polymerized (e.g., crosslinked) acrylate or methacrylate. In some of these embodiments, the acrylate or methacrylate is selected from the group consisting of tricyclodecane dimethanol diacrylate, 3- (acryloxy) -2-hydroxy-propyl methacrylate, triacryloxyethyl isocyanurate, glycerol (3) glyceryl diacrylate, propoxylated (5, 5) glyceryl (meth) acrylate, diacrylate, ethoxylated trimethylolpropane diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, propoxylated Diacrylate, propoxylated (3) trimethylolpropane diacrylate, propoxylated (6) trimethylolpropane diacrylate), trimethylolpropane diacrylate, trimethylolpropane triacrylate, di - trimethylol propane tetraacrylate, dipentaerythritol pentaacrylate, or It is a combination of these.

Useful methods for in situ crosslinking after flash evaporation and deposition are described, for example, in U.S. Patent No. 4,696,719 (Bischoff), 4,722,515 (Ham), 4,842,893 5,097,800 (Show et al.), 5,125,138 (Show et al.), 5,440,446 (Showa et al.), 4,954,371 (Alias), 5,018,048 (Show et al.), 5,547,908 (Furuzawa et al.), 6,045,864 (Lyons et al.), 6,231,939 (Show et al.), And 6,214,422 (Alias); International Patent Application Publication WO 00/26973 (Delta V Technologies, Inc.); D. G. Shaw and M. G. Langlois, "A New Vapor Deposition Process for Coating Paper and Polymer Webs", 6th International Vacuum Coating Conference (1992); D. G. Shaw and M. G. Langlois, "A New High Speed Process for Vapor Depositing Acrylate Thin Films: An Update ", Society of Vacuum Coaters 36th Annual Technical Conference Proceedings (1993); D. G. Shaw and M. G. Langlois, "Use of Vapor Deposited Acrylate Coatings to Improve the Barrier Properties of Metallized Film", Society of Vacuum Coaters 37th Annual Technical Conference Proceedings (1994); D. G. Shaw, M. Roehrig, M. G. Langlois and C. Sheehan, "Use of Evaporated Acrylate Coatings to Smooth the Surface of Polyester and Polypropylene Film Substrates", RadTech (1996); J. Affinito, P. Martin, M. Gross, C. Coronado and E. Greenwell, "Vacuum deposited polymer / metal multilayer films for optical application", Thin Solid Films 270, 43-48 (1995); And J. Med. Can be found in "Polymer-Oxide Transparent Barrier Layers", Society of Vacuum Coaters 39th Annual Technical Conference Proceedings (1996), by D. Affinito, M. E. Gross, C. A. Coronado, G. L. Graff, E. N. Greenwell and P. M. Martin.

In some embodiments, an amino-functional silane can be added to at least one of the first or second polymeric layers. An amino-functional silane was added to the polymer layer to effectively improve the adhesion between the inorganic oxide layer and the polymer layer in the multilayer barrier film. The cyclic aza silane exhibited improved adhesion at aging of up to 250 hours, even at 85 < 0 > C and 85% relative humidity. See, for example, U.S. Patent Application Publication No. 2012-0003451 (Weigel et al.) And No. 2012-0003484 (Roehrig et al.), Each of which is incorporated herein by reference in its entirety. The secondary or tertiary amino-functional silane with at least two silane groups maintains the adhesion and resists delamination after aging at 85 DEG C and 85% relative humidity for 1000 hours. International Patent Application Publication No. WO2014 / 025983 (Spagnola et al.), Which is incorporated herein by reference in its entirety. In some embodiments in which at least one of the first or second polymeric layer comprises a polymerized (e.g., crosslinked) acrylate or methacrylate, the siloxane reaction product is an amino of the secondary or tertiary amino-functional silane And an amide bond formed from the reaction between tie and acrylate or methacrylate.

Typically, the oxide layer comprises at least one inorganic oxide. In addition, suitable inorganic materials that may be included are nitride, carbide, or boride of different atomic elements. Examples of inorganic materials included in the oxide layer include oxides, nitrates, nitrides, carbides of rare earth metals, metals of group IIIB, IVB, or VB, group IIA, IIIA, IVA, VA, VIA, VIIA, IB, , Or borides, or combinations thereof. Examples of suitable inorganic materials include silicon oxide, such as silica, aluminum oxide, e.g., alumina, titanium oxide, such as titania, indium oxide, tin oxide, indium tin oxide ("ITO"), tantalum oxide, , Niobium oxide, aluminum nitride, silicon nitride, boron nitride, aluminum oxynitride, silicon oxynitride, boron oxynitride, zirconium borate, titanium borosilicate, and combinations thereof. ITO is an example of a particular class of ceramic materials that can be made electrically conductive by appropriate selection of the relative proportions of each elemental component. In some embodiments, the oxide layer comprises at least one of silicon aluminum oxide or ITO. Although the barrier film disclosed herein includes at least one oxide layer between the first polymer layer and the second polymer layer, in some embodiments, an inorganic layer, such as an inorganic oxide layer, is applied to the topmost second polymer layer .

The oxide layer may be formed using techniques used in the field of film metallization, such as sputtering (e.g., cathode or planar magnetron sputtering), evaporation (e.g., resistance or electron beam evaporation), chemical vapor deposition, . In some embodiments, the oxide layer is formed using sputtering, e. G., Reactive sputtering. Improved barrier properties have been observed when oxide layers are formed by high energy deposition techniques such as sputtering, as compared to lower energy technologies such as conventional chemical vapor deposition processes. Without being bound by theory, the improved properties are believed to be due to film-forming species that reach the substrate with greater kinetic energy resulting from sputtering, resulting in lower porosity as a result of compression.

In some embodiments, the sputter deposition process may use a dual target powered by an alternating current (AC) power source in the presence of an inert and reactive gas, e.g., a gas atmosphere having argon and oxygen, respectively. The AC power supply alternates the polarity for each of the dual targets such that one target is the cathode and the other target is the anode for half of the AC cycle. In the next cycle, the polarity is switched between the dual targets. This switching occurs at a set frequency, for example about 40 kHz, but other frequencies can be used. The oxygen introduced into this process forms an oxide layer on both the substrate housing the inorganic composition and also on the surface of the target. The dielectric oxide can be charged during sputtering, which can interfere with the sputter deposition process. The polarity switching can neutralize the surface material that is sputtered from the target and can provide uniformity and better control of the deposited material.

In some embodiments, the sputter deposition process may use a target that is powered by a direct current (DC) power supply in the presence of inert and reactive gases, e.g., a gas atmosphere having argon and oxygen, respectively. The DC power supply supplies power (e.g., pulse power) to each cathode target independently of the other power supplies. In this aspect, each individual cathode target and corresponding material may be sputtered at different power levels to provide additional control of composition through layer thickness. The pulsing aspect of the DC power supply is similar to the frequency behavior in AC sputtering, allowing control of high speed sputtering in the presence of reactive gas species such as oxygen. The pulsed DC power supply allows control of polarity switching, neutralizes the surface material sputtered from the target, and can provide uniformity and better control of the deposited material.

The barrier film may be deposited on a substrate in a roll-to-roll vacuum chamber similar to the system described in U.S. Patent No. 5,440,446 (Show et al.) And 7,018,713 (Padiyath et al. Layer, each of which is incorporated herein by reference in its entirety. Deposition of the layer can be done in-line, and once through the system. In some cases, the barrier film may pass the system a few times to form a multilayer barrier film with several die attach.

Examples of useful first polymer film substrates on which the barrier film is disposed include, for example, polyester, polyacrylates (e.g., polymethylmethacrylate), polycarbonate, polypropylene, high density or low density polyethylene, polysulfone , Polyether sulfone, polyurethane, polyamide, polyvinyl butyral, polyvinyl chloride, fluoropolymers (such as polyvinylidene difluoride and polytetrafluoroethylene), polyethylene sulfides, aerials of ethylene and norbornene (For example, available from Topas Advanced Polymers, Florence, Kentucky, USA as "TOPAS COC"), and epoxy, cellulose derivatives , Polyimide, polyimide benzoxazole, and thermosetting fillers such as polybenzoxazole .

In some embodiments, the first polymeric film substrate is selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, polyetheretherketone, polyaryletherketone, polyacrylate, polyetherimide, polyarylsulfone, polyether sulfone, polyamideimide, At least one of tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer, or polyvinylidene fluoride, , Any of which may optionally be heat-stabilized.

In some embodiments, the first polymeric film substrate is selected from the group consisting of polyethylene terephthalate (PET), polyethylene naphthalate (PEN), thermostable PET, thermostable PEN, polyoxymethylene, polyvinylnaphthalene, polyetheretherketone, At least one of polycarbonate, polymethyl methacrylate, poly-alpha-methylstyrene, polysulfone, polyphenylene oxide, polyetherimide, polyethersulfone, polyamideimide, polyimide, or polyphthalamide . In some embodiments, the substrate comprises PET.

For example, thermal stabilization of the substrate may be performed using heat setting, annealing under tension, or other techniques to prevent shrinkage to at least the thermal stabilization temperature if the polymer film is not constrained have.

In some embodiments, the first polymer film substrate is a multilayer optical film ("MOF"), such as those described in U.S. Patent Application Publication No. 2012-0003451 (Weigel et al.).

The substrate can have various thicknesses, for example from about 0.01 millimeters (mm) to about 1 mm. However, the substrate may be considerably thicker if, for example, a self-supporting article is required. Such articles may also conveniently be prepared by laminating or otherwise bonding the disclosed film made using a flexible substrate to a thicker, more flexible, non-rigid or less flexible support.

In some embodiments, the flatness and continuity of the first polymeric layer (and also the respective oxide layer and second polymeric layer) and its adhesion to underlying substrate or layer is determined by appropriate pretreatment of the first polymeric film substrate ≪ / RTI > Examples of suitable pretreatment methods include electrical discharge (e.g., plasma, glow discharge, corona discharge, dielectric barrier discharge, or atmospheric pressure discharge) in the presence of a suitable reactive or non-reactive atmosphere; Chemical pretreatment or flame pretreatment. These pretreatments help to make the surface of the underlying layer more soluble in the formation of the subsequently applied polymer layer (or inorganic layer). Plasma pretreatment may be particularly useful.

In some embodiments, a separate tie layer, which may have a different composition than the first polymer layer, may also be used on top of the substrate or underlying layer to improve adhesion. The adhesion promoting layer may be, for example, a layer of a separate polymeric layer or a metal-containing layer, such as a metal, metal oxide, metal nitride or metal oxynitride. The tie layer may have a thickness of a few nanometers (e.g., 1 or 2 nm) to about 50 nm, and may be thicker if necessary.

The desired chemical composition and thickness of the first polymer layer will depend in part on the nature of the substrate and the surface topography. Typically, the thickness is sufficient to provide a flat, defect-free surface to which a subsequent oxide layer may be applied. For example, the first polymer layer may have a thickness of a few nm (e.g., 2 or 3 nm) to about 5 micrometers, and may be thicker if necessary.

The major surface of the barrier film is bonded to the second polymeric film substrate using the pressure sensitive adhesive according to the present invention. The second polymeric film substrate may form a topsheet, for example, in a barrier assembly for a photovoltaic device. Useful materials from which the topsheet can be formed include polyesters, polycarbonates, polyethers, polyimides, polyolefins, fluoropolymers, and combinations thereof.

In embodiments in which the barrier assembly according to the invention is used, for example, for encapsulation of photovoltaic devices, the top sheet is typically preferably resistant to degradation by ultraviolet (UV) light and weathering. Photo-oxidative degradation caused by UV light (for example, in the range of 280 to 400 nm) may result in degradation of the optical and mechanical properties of the polymer film and color change. The topsheet described herein can provide, for example, a durable weatherproof topcoat for photovoltaic devices. The substrate is generally abrasion-resistant and impact-resistant, and can prevent deterioration of the photovoltaic device when exposed to extreme outdoor weather, for example.

Various stabilizers can be added to the topsheet to improve its resistance to UV light. Examples of such stabilizers include at least one of an ultraviolet absorber (UVA) (e.g., a redshift UV absorber), a hindered amine light stabilizer (HALS), or an antioxidant. These additives are described in further detail below. In some embodiments, the phrase "resistant to degradation by ultraviolet light" means that the topsheet comprises at least one ultraviolet absorber or hindered amine light stabilizer. In some embodiments, the phrase "resistant to degradation by ultraviolet light" means that the topsheet reflects at least 50% of incident ultraviolet light over a range of at least 30 nanometers in the wavelength range of at least 300 nanometers to 400 nanometers Or < RTI ID = 0.0 > absorbing < / RTI > In some of these embodiments, the topsheet need not comprise UVA or HALS.

In some embodiments, the second polymeric film substrate in the assembly disclosed herein comprises a fluoropolymer. Fluoropolymers typically exhibit resistance to UV degradation even in the absence of stabilizers such as UVA, HALS, and antioxidants. Useful fluoropolymers include ethylene-tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer (THV ), Polyvinylidene fluoride (PVDF), blends thereof, and blends of these and other fluoropolymers.

The substrate comprising the fluoropolymer may also comprise a non-fluorinated material. For example, a blend of polyvinylidene fluoride and polymethylmethacrylate may be used. Useful flexible visible and infrared light-transmissive substrates also include multilayer film substrates. The multilayer film substrate may have different fluoropolymers in different layers, or may include at least one fluoropolymer layer and at least one non-fluorinated polymer layer. The multilayer film may comprise several layers (e.g., two or more layers), or may include more than 100 layers (e.g., a total of 100 to 2000 layers or more). The different polymers in the different multilayer film substrates can be used in a wide range of wavelengths, for example, in the range of 300-400 nm, for example, in a substantial amount (e.g., 30, 40, or 40 nm) as described in, for example, U.S. Patent No. 5,540,978 (Schrenk) , Or 50% or more) of UV light.

Useful topsheets comprising fluoropolymers are described, for example, in U.S. Pat. TEFZEL ETFE " and " TEDLAR "from EI duPont De Nemours and Co., Dyneon LLC, Oakdale, Minn. Dyneon THV ", "Dyneon FEP ", and" Dyneon PVDF "from St. Gobain Performance Plastics, Wayne, New Jersey, USA under the trade designations " DYNEON ETFE & "NORTON ETFE" was purchased from Asahi Glass under the trade name "CYTOPS" and from Denka Kagaku Kogyo KK in Tokyo, Japan under the trade name "Denka DX Film" Quot; DENKA DX FILM ".

In some embodiments, the second surface of the first polymeric film substrate is attached to the photovoltaic cell using an encapsulant layer. Other encapsulants may be useful, but in some embodiments, the encapsulant layer comprises ethylene vinyl acetate.

In some embodiments, the PSA layer in the assemblies disclosed herein is at least 0.005 mm thick (in some embodiments, 0.01, 0.02, 0.03, 0.04, or 0.05 mm or greater). In some embodiments, the PSA layer has a thickness of at most about 0.2 mm (in some embodiments, at most 0.15, 0.1, or 0.075 mm). For example, the thickness of the PSA layer may range from 0.005 mm to 0.2 mm, from 0.005 mm to 0.1 mm, or from 0.01 to 0.1 mm.

In addition to serving as a convenient means for attaching the second polymeric film substrate to the barrier film within the assemblies disclosed herein, the PSA also includes a second polymeric film substrate, which may be a fluoropolymer, But also serves to protect the barrier assembly from thermal stresses that may be caused by CTE mismatch between the first polymeric film substrate. The PSA layer according to the invention, including ultraviolet-absorbing oligomers, further provides protection against barrier film from degradation by UV light.

The UV resistance of PSA and the durability of the protection provided can be evaluated, for example, using an accelerated weathering study. Accelerated weathering studies are generally carried out on film in accordance with the standard practice for exposing non-metallic materials to accelerated test equipment using laboratory light sources as described in ASTM G-155. sources "). The ASTM technology mentioned is considered as a robust predictor of outdoor durability, that is, it correctly grades the performance of the material. One mechanism for detecting changes in physical properties is to use a weather-resistant cycle as described in ASTM G155 and a D65 light source operating in a reflected mode. Under the mentioned test, and when the UV protective layer is applied to the article, the article has a b * value obtained using the CIE L * a * b * space of less than 5, before significant cracking, peeling, delamination or haze commences Or less, or less than or equal to 4, less than or equal to 3, or less than or equal to ² .

Some embodiments of the present invention

In a first embodiment, the present invention provides a composition comprising a pressure-sensitive adhesive and a blend of ultraviolet light-absorbing oligomers, wherein the ultraviolet light-absorbing oligomer comprises

A first divalent unit comprising a pendant ultraviolet absorber; And

A second divalent unit represented by the formula:

;

;

In this formula,

R ¹ is hydrogen or methyl;

R ² is alkyl having from 4 to 20 carbon atoms,

Wherein the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive comprising the second divalent unit, and for at least some of the second divalent units in the pressure sensitive adhesive, R ² is the second divalent unit in the ultraviolet- Alkyl having the same number of carbon atoms as at least some of the units.

In a second embodiment, the present invention provides a composition according to the first aspect, wherein R < ² > is an alkyl having 8 carbon atoms.

In the third embodiment, the present invention provides the composition of the first or second embodiment, wherein the number average molecular weight of the ultraviolet-absorbing oligomer is not more than 1/2 of the number average molecular weight of the pressure-sensitive adhesive.

In a fourth embodiment, the present invention provides a process for producing a pressure-sensitive adhesive, wherein at least one of the pressure-sensitive adhesive or the ultraviolet light-absorbing oligomer comprises a pendant carboxylic acid, a hydroxyl, an aminocarbonyl, an alkylaminocarbonyl or a dialkylaminocarbonyl group A composition according to any one of the first to third embodiments wherein the alkyl in the alkylaminocarbonyl or dialkylaminocarbonyl is optionally substituted by hydroxyl, to provide.

In a fifth embodiment, the present invention provides a composition according to the fourth aspect, wherein both the pressure-sensitive adhesive and the ultraviolet-light absorbing oligomer include the same third divalent unit.

In a sixth embodiment, the present invention provides the composition of any of the first to fifth embodiments, wherein the pendant ultraviolet absorber comprises triazine, benzophenone, or benzotriazole.

In a seventh embodiment, the present invention provides a composition according to any one of the first to sixth embodiments, wherein each first divalent unit is independently represented by the following formula:

In this formula,

R ¹ is independently hydrogen or methyl;

V is O or NH;

X is a bond, alkylene, or alkyleneoxy, wherein said alkylene or alkyleneoxy has from 1 to 10 carbon atoms and optionally one or more -O- groups intervened and optionally substituted by hydroxyl groups;

R is alkyl having 1 to 4 carbon atoms;

n is 0 or 1;

Z is a benzoyl group optionally substituted by hydroxyl, alkyl, halogen, or hydroxyl; A 4,6-bisthenyl [1,3,5] triazin-2-yl group wherein each phenyl is independently optionally substituted by one or more alkyl or alkoxy groups; Or a 2H-benzotriazol-2-yl group optionally substituted by one or more halogens.

In an eighth embodiment, the present invention provides a composition according to any one of the first to seventh embodiments, wherein at least some of the first divalent units in the ultraviolet light-absorbing oligomer include different Z groups do.

In a ninth embodiment, the present invention relates to the first to eighth embodiments wherein the ultraviolet light-absorbing oligomer is present in the composition in an amount ranging from 0.5% by weight to 25% by weight based on the total weight of the composition. Lt; RTI ID = 0.0 > of < / RTI >

In a tenth embodiment, the present invention is directed to a composition comprising a second ultraviolet light-absorbing oligomer, wherein the composition comprises a second ultraviolet light-absorbing oligomer different from the first ultraviolet light-absorbing oligomer in the blend, The composition of any of the first to ninth embodiments is provided wherein the first divalent unit in the oligomer comprises different Z groups.

In an eleventh embodiment, the present invention relates to a process for the preparation of a composition, wherein the ultraviolet light-absorbing oligomer and the different second ultraviolet light-absorbing oligomer are present in the composition in a total amount ranging from 1% by weight to 25% The composition of the tenth embodiment is provided.

In a twelfth embodiment, the present invention relates to any one of the first to eleventh embodiments, wherein the ultraviolet absorber is present in the composition in an amount ranging from 0.5% by weight to 15% by weight based on the total weight of the composition One composition is provided.

In a thirteenth aspect, the present invention provides an article comprising the composition of any one of the first to twelfth embodiments.

In a fourteenth embodiment, the present invention provides the article of the thirteenth aspect, wherein the article is a photovoltaic element.

In a fifteenth embodiment, the present invention provides the article of the thirteenth or fourteenth embodiment, wherein the composition is disposed on at least a part of the surface of the film.

In a sixteenth embodiment, the present invention provides the article of the fifteenth embodiment, wherein the film is at least one of a graphic film, a construction film, a window film, or a vehicle wrap.

In a seventeenth embodiment, the present invention provides the article of the fifteenth embodiment, wherein the film is a barrier film.

In an eighteenth embodiment, the present invention provides an assembly,

A first polymeric film substrate having a first surface and a second surface opposite the first surface;

A barrier film disposed on a first surface of the first polymeric film;

A pressure sensitive adhesive layer having a first surface and a second surface opposite the first surface, wherein a first surface of the pressure sensitive adhesive is disposed on the barrier film opposite the first polymer film substrate; And

And a second polymeric film substrate disposed on the second surface of the pressure sensitive adhesive layer,

Wherein the pressure sensitive adhesive layer comprises an ultraviolet light-absorbing oligomer, and the ultraviolet light-absorbing oligomer comprises

A first divalent unit comprising a pendant ultraviolet absorber; And

A second divalent unit represented by the formula:

In this formula,

R ¹ is hydrogen or methyl;

R ² is alkyl having from 4 to 20 carbon atoms.

In a nineteenth embodiment, the present invention provides the nineteenth embodiment wherein the pressure-sensitive adhesive layer is formed of a combination of acrylate, silicone, polyisobutylene, urea, natural rubber, or a combination of styrene and hydrogenated polybutadiene, hydrogenated polyisoprene or hydrogenated polybutadiene and polyisoprene ≪ / RTI > of ABA triblock copolymer.

In a twentieth embodiment, the present invention provides an assembly according to the eighteenth or nineteenth aspect, wherein the pressure-sensitive adhesive layer comprises an acrylic pressure-sensitive adhesive.

In the 21st embodiment, the present invention, the pressure-sensitive adhesive layer on at least a portion of the second divalent units in the pressure-sensitive adhesive, comprising the acrylic pressure sensitive adhesive to the second 2 comprises the units, R ² Is an alkyl having the same number of carbon atoms as at least a part of the second divalent units in the ultraviolet light-absorbing oligomer.

In a twenty-second embodiment, the present invention provides an assembly according to any one of the eighteenth to twenty-first aspects, wherein R < ² > is alkyl having eight carbon atoms.

In a twenty-third embodiment, the present invention provides an assembly according to any one of the eighteenth to twenty-second aspects, wherein the number average molecular weight of the ultraviolet light-absorbing oligomer is not more than 1/2 of the number average molecular weight of the pressure- do.

In a twenty-fourth aspect, the present invention provides a method for producing a pressure-sensitive adhesive, wherein at least one of the pressure-sensitive adhesive or the ultraviolet light-absorbing oligomer comprises a pendant carboxylic acid, a hydroxyl, an aminocarbonyl, an alkylaminocarbonyl, or a dialkylaminocarbonyl group Further comprising an assembly of any one of the twentieth to twenty-third embodiments wherein the alkyl in the alkylaminocarbonyl or dialkylaminocarbonyl is optionally substituted by hydroxyl. to provide.

In the twenty-fifth embodiment, the present invention provides the assembly of the twenty-fourth embodiment, wherein both the pressure-sensitive adhesive and the ultraviolet light-absorbing oligomer include the same third divalent unit.

In a twenty-sixth embodiment, the present invention provides the assembly of any one of the eighteenth to twenty-fifth aspects, wherein the pendant ultraviolet absorber comprises triazine, benzophenone, or benzotriazole.

In a twenty-seventh embodiment, the present invention provides an assembly according to any one of the eighteenth to twenty-sixth aspects, wherein each first divalent unit is independently represented by the following formula:

In this formula,

R ¹ is independently hydrogen or methyl;

V is O or NH;

X is a bond, alkylene, or alkyleneoxy, wherein said alkylene or alkyleneoxy has from 1 to 10 carbon atoms and optionally one or more -O- groups intervened and optionally substituted by hydroxyl groups;

R is alkyl having 1 to 4 carbon atoms;

n is 0 or 1;

Z is a benzoyl group optionally substituted by hydroxyl, alkyl, halogen, or hydroxyl; A 4,6-bisthenyl [1,3,5] triazin-2-yl group wherein each phenyl is independently optionally substituted by one or more alkyl or alkoxy groups; Or a 2H-benzotriazol-2-yl group optionally substituted by one or more halogens.

In a twenty-eighth embodiment, the present invention provides an assembly of the twenty-seventh embodiment, wherein at least some of the first dichroic units in the ultraviolet light-absorbing oligomer comprise different Z groups.

In a twenty-ninth embodiment, the present invention provides a pressure-sensitive adhesive composition, wherein the pressure-sensitive adhesive layer includes a second ultraviolet-absorbing oligomer different from the first ultraviolet-absorbing oligomer in the blend, - the assembly of the twenty seventh or twenty-eighth embodiment, wherein said first divalent unit in the absorbing oligomer comprises different Z groups.

In a thirtieth embodiment, the present invention relates to a pressure-sensitive adhesive composition, wherein the ultraviolet light-absorbing oligomer and the different second ultraviolet light-absorbing oligomer are contained in a total amount ranging from 1% by weight to 25% by weight based on the total weight of the pressure- There is provided an assembly according to the twenty-ninth embodiment.

In the 31st embodiment, the present invention is the 18th embodiment wherein the ultraviolet light-absorbing oligomer is present in the pressure-sensitive adhesive layer in an amount ranging from 0.5% by weight to 25% by weight based on the total weight of the pressure- To 30 < th > embodiments.

In a thirtieth embodiment, the present invention is the ultraviolet absorber according to any one of the eighteenth to thirty-first embodiments wherein the ultraviolet absorber is present in the pressure-sensitive adhesive layer in an amount ranging from 0.5% by weight to 15% by weight based on the total weight of the composition. / RTI > of the present invention.

In a thirty-third embodiment, the present invention provides an assembly according to any of the embodiments 18-32, wherein said barrier film comprises at least a first and a second polymeric layer separated by an inorganic barrier layer.

In a thirty-fourth aspect, the present invention provides the assembly of the thirty third embodiment, wherein the inorganic barrier layer is an oxide layer.

In a thirtieth embodiment, the present invention is directed to any one of embodiments 18 to 34 wherein the barrier film comprises a plurality of alternating layers of a second polymeric layer and an oxide layer on the first polymeric film substrate. Assembly.

In a thirty-sixth embodiment, the present invention provides a method of producing a film, wherein the first polymer film substrate is at least one selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, polyetheretherketone, polyaryletherketone, polyacrylate, polyetherimide, polyarylsulfone, , Polyamideimide, polyimide, ethylene-tetrafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer, or polyvinylidene Fluoride, and any of which may optionally be heat-stabilized. ≪ Desc / Clms Page number 24 >

In a thirty-seventh embodiment, the present invention provides an assembly according to any one of the thirty-third to thirty-sixth aspects, wherein at least one of the first or second polymer layers comprises polymerized acrylate or methacrylate to provide.

In a thirty-eighth embodiment, the present invention is directed to a composition according to the thirty-eighth aspect, wherein the acrylate or methacrylate is selected from the group consisting of tricyclodecane dimethanol diacrylate, 3- (acryloxy) -2-hydroxy-propyl methacrylate, (3) glyceryl diacrylate, propoxylated (5, < RTI ID = 0.0 > pentyloxypropyl) < / RTI & 5) glyceryl diacrylate, propoxylated (3) trimethylolpropane diacrylate, propoxylated (6) trimethylolpropane diacrylate, trimethylolpropane diacrylate, trimethylolpropane triacrylate Di-trimethylol propane tetraacrylate, dipentaerythritol pentaacrylate , Or provide a combination of both of, the 37th embodiment of the assembly.

In a thirty-ninth embodiment, the present invention provides an assembly according to any of the thirty-third to thirty-eighth embodiments, wherein at least one of said first or second polymeric layers comprises a siloxane reaction product of an amino- to provide.

In a 40th embodiment, the present invention provides an assembly of the 39th embodiment, wherein said siloxane reaction product shares a siloxane bond with said oxide layer.

In a 41st embodiment, the present invention provides a method of producing a laminated film, wherein the second polymer film substrate is an ethylene-tetrafluoroethylene copolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, a tetrafluoroethylene-hexafluoropropylene-vinyl Or a polyvinylidene fluoride, and at least one of polyvinylidene fluoride, polyvinylidene fluoride copolymer, polyvinylidene fluoride copolymer, or polyvinylidene fluoride.

In a 42nd embodiment, the present invention provides an assembly according to any one of the 18th to 41st embodiments, wherein the second surface of the first polymeric film base material is disposed on the photovoltaic cell.

In a 43rd embodiment, the present invention provides the assembly of the 42nd embodiment, wherein the photovolari- cular cell is a CIGS battery.

In a 44 th embodiment, the present invention provides the assembly of the 42nd or 43rd embodiment, wherein the second surface of the first polymeric film substrate is attached to the photovoltaic cell using an encapsulant layer.

In a forty-fifth embodiment, the present invention provides the assembly of the fortieth embodiment, wherein the encapsulant layer comprises ethylene vinyl acetate.

In a 46 th embodiment, the present invention provides a barrier film comprising a barrier film having an oxygen transmission rate of less than 0.005 g / m ² / day at 23 ° C and 90% relative humidity, or 0.005 g / m ² / day Wherein the water vapor transmission rate is at least one of a water vapor permeability and a water vapor permeability of less than a predetermined value.

Embodiments of the compositions and methods disclosed herein are further illustrated by the following examples, but it should be understood that the specific materials and amounts thereof recited in these examples, as well as other conditions and details, It should not be.

Example

Molecular weight measurement

In the following Oligomer Examples, molecular weight was determined by comparison with linear polystyrene polymer standards using gel permeation chromatography (GPC). GPC measurements were performed on a Waters Alliance 2695 system (available from Waters Corporation, Milford, Mass.) With a 5 micrometer styrene solution having pore sizes of 10,000, 1000, 500, and 100 angstroms Four 300 millimeter (mm) x 7.8 mm linear columns of divinylbenzene copolymer particles (available from Polymer Laboratories, Shropshire, UK, under the trade designation "PLGEL" Respectively. A refractive index detector (Model 410) from Waters Corporation was used at 40 占 폚. A 50 milligram (mg) sample of the oligomer in ethyl acetate was diluted with 10 milliliters (mL) of tetrahydrofuran (inhibited by 250 ppm of BHT) and filtered through a 0.45 micrometer syringe filter. A sample volume of 100 microliters was injected onto the column, and the column temperature was 40 占 폚. A flow rate of 1 mL / min was used and the mobile phase was tetrahydrofuran. Molecular weight correction was performed using a narrow dispersion polystyrene standard with a peak average molecular weight in the range of 3.8 × 10 ⁵ grams / mole to 580 grams / mole. Calibration and molecular weight distribution calculations were performed using suitable GPC software using a third order polynomial fit to the molecular weight calibration curve. Each reported result is an average of duplicate experimental injections.

Glass transition temperature

For the oligomeric examples below, the glass transition temperature was measured by differential scanning calorimetry (DSC) using a Q2000 differential scanning calorimeter obtained from TA Instruments, Newcastle, Delaware, USA. The glass transition temperature was determined using a modulated DSC having a modulation amplitude of +/- 1 DEG C / min and a ramp rate of 3 DEG C / min.

PREPARATION EXAMPLE 1

2-yl] -3-hydroxy-phenoxy} -ethylacrylate < / RTI > ester

Part A

A three-liter three-neck round bottom flask was equipped with a temperature probe, condenser and mechanical stirrer. The flask was charged with 500 grams (1.26 moles) of 2,4-di- (2,4-dimethylphenyl) -6- (2,4-dihydroxyphenyl) -triazine, 124 grams (1.4 moles) , 18 grams (0.085 mole) of tetraethylammonium bromide, and 475 grams of dimethylformamide. The batch was heated to < RTI ID = 0.0 > 150 C < / RTI > and held at that temperature for 5 hours. The occurrence of CO ₂ from the batch was observed. After 5 hours, 15 grams of additional ethylene carbonate and 2 grams of additional tetraethylammonium bromide were added. The batch was heated at 150 占 폚 for 3 hours, followed by the addition of 15 grams of additional ethylene carbonate and 2 grams of additional tetraethylammonium bromide. The batch was heated at 150 < 0 > C for an additional 3 hours, after which time no more material was observed by thin layer chromatography.

The batch was allowed to cool to 80 DEG C and 1360 grams of isopropanol (IPA) was added with good stirring. The mixture was cooled to room temperature and the solid product was collected on a Buchner funnel by filtration. The solid product was dissolved in 1000 grams of water and IPA, respectively, stirred well, and collected on a Buchner funnel by filtration. The product was air dried to give 540 grams (96%) of an off-white solid product, 2- [4,6-bis- (2,4-dimethylphenyl) - [1,3,5] triazin- -One] -5- (2-hydroxyethoxy) phenol (mp = 172-173 ° C). The product was used without further purification.

Part B

A two-liter three-neck round bottom flask was equipped with a temperature probe, a Dean-Stark trap with a condenser, and a mechanical stirrer. The flask was charged with 170 grams (0.385 mole) of 2- [4,6-bis- (2,4-dimethylphenyl) - [1,3,5] triazin- (2-hydroxyethoxy) phenol, 780 grams of toluene, 0.24 grams of a 4-methoxyphenol (MEHQ) inhibitor, 0.38 grams of a phenothiazine inhibitor, 8.5 grams of p-toluenesulfonic acid, and 30.5 grams 0.42 mol) of acrylic acid. The batch is heated with moderate stirring at reflux (about 115 ° C) for 6 hours, and azeotroped water can be collected in the Dean-Stark trap. After 5 hours, 5 grams of additional acrylic acid was added and the batch was heated for an additional 3 hours. In the analysis by thin layer chromatography, the batch was found to have no residual materials.

The batch was allowed to cool to 80 DEG C and a pre-mix of 25 grams of sodium carbonate in 300 grams of water was added. The reaction mixture was cooled to about 10 < 0 > C using an ice bath and the precipitated product was collected on a Buchner funnel by filtration. The solid was redissolved in a mixture of 800 grams of water and 200 grams of IPA, and the mixture was stirred well and filtered. The product was air dried to give 182 grams (96%) of a off-white solid product, 2- {4- [4,6-bis- (2,4-dimethyl- phenyl) - [1,3,5] triazin- -Yl] -3-hydroxyphenoxy} ethyl acrylate ester (mp = 126 DEG C to 128 DEG C) was obtained. This structure was confirmed by ¹ H NMR spectroscopy.

Preliminary Example 2

2- (4-benzoyl-3-hydroxyphenoxy) ethyl acrylate ester

Part A

A 5 liter 3 neck round bottom flask was equipped with a temperature probe, condenser and mechanical stirrer. The flask was charged with 500 grams (2.33 moles) of 2,4-dihydroxybenzophenone, 216 grams (2.45 moles) of ethylene carbonate, and 25 grams (0.12 moles) of tetraethylammonium bromide. The batch was heated to 140 < 0 > C and held at that temperature for 24 hours. The occurrence of CO ₂ from the batch was observed. In the analysis by thin layer chromatography, the batch was found to have no residual materials.

The batch was allowed to cool to 80 ° C and 1200 grams of isopropanol was added with good stirring. The batch temperature was maintained at about 60 DEG C and 2500 grams of water was added while maintaining a batch temperature of about 60 DEG C. [ The batch was cooled to room temperature with slow stirring and the product was collected on a Buchner funnel by filtration. The solid product was redissolved in 1000 grams of water and 200 grams of IPA, well stirred, and collected on a Buchner funnel by filtration. The product was air dried to give 545 grams (90%) of a off-white solid product, 2-hydroxy-4- (2-hydroxyethyl) benzophenone (mp = 88 ° C to 89 ° C). The product was used without further purification.

Part B

A two-liter three-neck round bottom flask was equipped with a temperature probe, a Dean-Stark trap with condenser, and a mechanical stirrer. The flask was charged with 200 grams (0.77 moles) of 2-hydroxy-4- (2-hydroxyethyl) benzophenone, 850 grams of toluene, 0.48 grams of MEHQ inhibitor, 0.77 grams of phenothiazine Inhibitor, 17 grams of p-toluenesulfonic acid, and 61.4 grams (0.85 mole) of acrylic acid. The batch was heated with moderate stirring at reflux (about 115 [deg.] C) for 6 hours, and azeotropic distilled water was collected in the Dean-Stark trap. After 5 hours, 5 grams of additional acrylic acid was added and the batch was heated for an additional 3 hours. In the analysis by thin layer chromatography, the batch was found to have no residual materials.

The batch was cooled to 80 DEG C and a pre-mixture of 25 grams of sodium carbonate in 300 grams of water was added. The batch was phase separated and the lower aqueous layer was removed. The organic layer was washed with a mixture of 25 grams of sodium chloride in 300 grams of water. The solvent was stripped using a rotary evaporator. The residual brown oil product was dissolved in 230 grams of IPA and heated to about < RTI ID = 0.0 > 60 C < / RTI > The mixture was gently stirred and cooled to -10 [deg.] C to crystallize the off-white solid product. The product was air dried to give 217 grams (90%) of a off-white solid product, 2- (4-benzoyl-3-hydroxyphenoxy) ethyl acrylate ester (mp = 126 DEG C to 128 DEG C). This structure was confirmed by ¹ H NMR spectroscopy.

Preliminary Example 3

2- [4- (4,6-diphenyl) - [1,3,5] triazin-2-yl] -3-hydroxy-phenoxy} -ethylprop-

Part A

A two-liter three-neck round bottom flask was equipped with a temperature probe, condenser and mechanical stirrer. The flask was charged with 400 grams (1.17 moles) of 4- (4,6-diphenyl-1,3,5-triazin-2-yl) benzene-1,3-diol, 115.5 grams (1.31 moles) Borate, 16.7 grams (0.085 mole) of tetraethylammonium bromide and 440 grams of dimethylformamide (DMF). The batch was heated to 150 < 0 > C and held at that temperature for 5 hours. The occurrence of CO ₂ from the batch was observed. After 5 hours, 10 grams of additional ethylene was added. The batch was heated at 150 占 폚 for 3 hours, followed by the addition of 15 grams of additional ethylene carbonate and 2 grams of additional tetraethylammonium bromide. The batch was heated at 150 < 0 > C for an additional 3 hours, after which time no more material was observed by thin layer chromatography.

The batch was allowed to cool to 80 DEG C and 730 grams of isopropanol (IPA) was added. The mixture was concentrated and the stirring was improved by the addition of a 50/50 IPA / water mixture. The solid product was then collected on a Buchner funnel by filtration. The solid product was dissolved in 2500 grams of DMF, heated at reflux, cooled to room temperature, and collected on a Buchner funnel by filtration. The product was air dried to give 373 grams (83%) of a off-white solid product, 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- (2-hydroxyethoxy) Phenol.

Part B

A two-liter three-neck round bottom flask was equipped with a temperature probe, a Dean-Stark trap with condenser, and a mechanical stirrer. The flask was charged with 150 grams (0.389 moles) of 2- (4,6-diphenyl-1,3,5-triazin-2-yl) -5- (2-hydroxyethoxy) Phenol, 790 grams of toluene, 0.24 grams of a 4-methoxyphenol (MEHQ) inhibitor, 0.38 grams of phenothiazine inhibitor, 8.5 grams of p-toluenesulfonic acid, and 30.8 grams (0.43 mole) of acrylic acid. The batch was heated with moderate stirring at reflux (about 115 [deg.] C) for 6 hours, and azeotropic distilled water was collected in the Dean-Stark trap. After 5 hours, 5 grams of additional acrylic acid was added and the batch was heated for an additional 3 hours. In the analysis by thin layer chromatography eluting with 50/50 ethyl acetate / hexanes, the batch appeared to have no residual materials.

The batch was allowed to cool to 80 DEG C and 65 grams of triethylamine was added. The batch was heated at reflux at atmospheric pressure to remove most of the toluene. The pot temperature was 120 DEG C and about 650 grams of toluene was collected. The batch was allowed to cool to 75 DEG C and 500 grams of IPA was added. The mixture was heated at reflux (about 82 [deg.] C) to azeotropically remove toluene and IPA. About 500 grams of solvent was collected. The reaction mixture was cooled to about 20 C using an ice bath and 500 grams of IPA was added with stirring. The precipitated product was collected on a Buchner funnel by filtration. The solids were redissolved in a mixture of 700 grams of water and 700 grams of IPA, the mixture was stirred well and filtered. The product was air dried to give 161.8 grams (95%) of a light yellow solid product (mp = 125 ° C to 127 ° C).

For further purification, about 90 grams of light yellow solid was combined with 1200 grams of MEK and heated to 40 占 폚. Five grams of charcoal was added and the mixture was well stirred and filtered through a filter aid bed. The solvent was removed using a rotary evaporator, followed by the addition of 400 grams of IPA. The mixture is stirred well and the solid product 2- [4- (4,6-diphenyl) - [1,3,5] triazin-2-yl] -3- hydroxy- phenoxy} 2-enoate was collected by filtration. mp = 126 [deg.] C to 128 [deg.] C. This structure was confirmed by ¹ H NMR spectroscopy.

Oligomer Preparation Example 1

76 wt% isooctyl acrylate, 4 wt% acrylic acid, 12 wt% preliminary Example 1, and 8 wt% random copolymer of preliminary Example 2

(380 g, available from 3M Company, St. Paul, MN, USA) in a 3 liter flask equipped with a thermocouple, overhead stirrer, and reflux condenser under positive nitrogen flow was charged with 60 g of preliminary Example 1, 40 g of Preliminary Example 2, 12.5 g of 2,2'-azobis (2-methylbutyronitrile) (available from EI DuPont de Nemours, Wilmington, Del. Quot; VAZO 67 "from the And Company), and 500 g of ethyl acetate. After the material addition was complete, the flask was held under a positive nitrogen pressure. The material was heated at 74 占 폚 for 19 hours. The contents of the flask were removed and the solids were measured. 5.77 g of the solution was dried to give 2.76 g of a solid (47% solids). The resin solution was poured into a plastic bottle to obtain 1029 g of a solution. One glass transition temperature was observed at -23.6 ° C using DSC according to the method described above with scans from -100 ° C to 150 ° C. The molecular weight of the oligomers was determined by GPC (THF, EMD Omnisolve, 2c PL-gel-300 x 7.5 mm, polystyrene standards): Mw = 271,000, Mn = 114,000, Mz = 551,300, and The polydispersity is 2.38.

Oligomer Preparation Example 2

80% by weight of isooctyl acrylate and 20% by weight of random copolymer of preliminary Example 1

100 g of isooctyl acrylate (400 g, available from 3M Company, St. Paul, MN, USA) was placed in a 3 liter flask equipped with a thermocouple, overhead stirrer and reflux condenser under positive nitrogen flow Example 1 A mixture of 6.0 g of 2,2'-azobis (2-methylbutyronitrile) (obtained from E. D. Du Pont de Nemours & Co. under the trade designation "Vazo 67") and 500 g of ethyl acetate ≪ / RTI > After the material addition was complete, the flask was held under a positive nitrogen pressure. The material was heated at 74 占 폚 for 19 hours. The contents of the flask were removed and the solids were measured. 4.59 g of the solution was dried to give 2.43 g of solid (53% solids). The resin solution was poured into a plastic bottle to obtain 943 g of a solution. One glass transition temperature was observed at -31.3 占 폚 using DSC according to the method described above with a scan from -100 占 to 150 占 폚. The molecular weight of the oligomer was determined by GPC (THF, IM di Omnisolv, 2c PL-gel-300 x 7.5 mm, polystyrene standards): Mw = 241,000, Mn = 99,490, Mz = 433,000, .

Oligomer Preparation Example 3

A random copolymer of 80 wt% isooctyl acrylate and 20 wt% 2- [2-hydroxy-5- [2- (methacryloyloxy) -ethyl] phenyl] -2H-benzotriazole

2- [2-Hydroxy-5- [2- (methacryloyloxy) -ethyl] phenyl] -2H-benzotriazole was obtained from TCI America, Portland, Oreg. (400 g, available from 3M Company, St. Paul, MN, USA) in a 3 liter flask equipped with a thermocouple, overhead stirrer and reflux condenser under positive nitrogen flow was charged with 100 g of 2 < RTI ID = - [2- (methacryloyloxy) -ethyl] phenyl] -2H-benzotriazole, 5.0 g of 2,2'-azobis (2-methylbutyronitrile) Available from E. I. Du Pont de Nemours & Company under the trade designation "Vazo 67"), and 500 g of ethyl acetate. After the material addition was complete, the flask was held under a positive nitrogen pressure. The material was heated at 74 占 폚 for 19 hours. The contents of the flask were removed and the solids were measured. 2.91 g of the solution was dried to give 1.49 g of a solid (51% solids). The resin solution was poured into a plastic bottle to obtain 993 g of a solution. One glass transition temperature was observed at -36.7 [deg.] C with a scan from -100 [deg.] C to 150 [deg.] C using DSC according to the method described above. The molecular weights of the oligomers were determined by GPC (THF, IM di Omnisolv, 2c PL-gel-300 x 7.5 mm, polystyrene standards): Mw = 574,100, Mn = 96,120, Mz = 1,663,000, .

Oligomer Preparation Example 4

80% by weight of isooctyl acrylate, 20% by weight of the random copolymer of Preparative Example 3

In a 1 liter flask equipped with a thermocouple, overhead stirrer, and reflux condenser under positive nitrogen flow, 40 g of isooctyl acrylate (available from ThysiA America) were added to 10 g of Example 3, 1 g Azobis (2-methylbutyronitrile) (available under the trade designation "VAZO 67" from E.I. du Pont de Nemours and Company, Wilmington, Del.) And 100 g of Ethyl acetate. After the material addition was complete, the flask was held under a positive nitrogen pressure. The material was heated at 74 占 폚 for 1 hour and then an additional 1 g of 2,2'-azobis (2-methylbutyronitrile) was added. The material was heated at 74 占 폚 for 18 hours. The contents of the flask were removed and the solids were measured. 4.13 g of the solution was dried to give 1.53 g of solid (37% solids). The resin solution was poured into a plastic bottle to obtain 134 g of a solution. One glass transition temperature was observed at -31.9 占 폚 using DSC according to the method described above with scans from -100 占 to 150 占 폚.

The oligomer may be incorporated into a pressure sensitive adhesive composition made from components including, for example, isooctyl acrylate.

Oligomer Preparation Example 5

80% by weight methyl methacrylate and 20% by weight random copolymer of the preliminary Example 1

Oligomer Preparation Example 1 was prepared by the general method described in U.S. Patent No. 5,986,011 (Ellis). In the first stage of the polymerization, the stainless steel reactor was charged with 64 grams of methyl methacrylate (available from Rohm and Haas, Philadelphia, Pa.), 16 grams of Preparative Example 1, 4.0 grams of Ethyl acetate, 0.08 grams of antioxidant, 2.4 grams of chain transfer agent isooctyl thioglycolate (IOTG), 0.34 grams of MEHQ (trade name) available from BASF of Floham Park, NJ, USA, available under the trade designation "Irganox 1010" , And E. Lee, Wilmington, Delaware, USA. Azobis (2,4-dimethylpentanenitrile), available from DuPont Dinemoa & Company under the tradename "Bazo 52 ". The reactor was sealed, oxygen was purged using nitrogen, and then maintained at about 100 psig nitrogen pressure. The reaction mixture was heated to 60 캜 in the first stage and then allowed to polymerize adiabatically to reach a maximum of 113 캜. When the reaction was complete, the mixture was cooled to below 50 < 0 > C.

Subsequently, a solution of various initiators dissolved in 18.64 grams of ethyl acetate (obtained from E. I. Du Pont de Nemours & Company under the trade designation "VAZO 52", 0.80 grams of 2,2'-azobis Dimethylpentanenitrile), 0.20 grams of 2,2'-azobis (2-methylbutanenitrile), available from E. I. Du Pont de Nemours & Company under the trade designation " 0.20 grams of 2,2'-azobis (cyclohexanecarbonitrile), available from Nemo & Company under the trade designation "VAZO 88", from Elf Atochem, Philadelphia, Pennsylvania, 0.16 grams of 2,5-dimethyl-2,5-di- (t-butylperoxy) hexane, available as LUPERSOL 101 ", available from Elf Atochem, 2,5-dimethyl-2,5-di- (t-butylperoxy) hexyne-3) and 1.13 grams of IOTG were added to the product of the first step . The reactor was sealed, oxygen was purged with nitrogen, and then maintained at 100 psig nitrogen pressure. The reaction mixture was heated to < RTI ID = 0.0 > 60 C < / RTI > After the reaction reached a peak temperature of 144 占 폚, the mixture was held at 145 占 폚 for 1 hour and discharged to an aluminum tray during hot. After cooling the material, the resulting solid polymer was beat with a hammer. The molecular weight of the oligomer was determined by GPC (THF, IM di Omnisolv, 2c PL-gel-300 x 7.5 mm, polystyrene standards): Mw = 108,700, Mn = 54,980, and polydispersity of 1.99.

Oligomer Preparation Example 6

A random copolymer of 80 wt% methyl methacrylate and 20 wt% 2- [2-hydroxy-5- [2- (methacryloyloxy) -ethyl] phenyl] -2H-benzotriazole

2- [2-Hydroxy-5- [2- (methacryloyloxy) -ethyl] phenyl] -2H-benzotriazole was obtained from TCI America, Portland, Oreg. Oligomer Preparation Example 2 was prepared by the general method described in U.S. Patent No. 5,986,011 (Ellis). In the first step of the polymerization, the stainless steel reactor was charged with 64 grams of methyl methacrylate (available from Rohm and Haas, Philadelphia, Pa.), 16 grams of 2- [2-hydroxy-5- [2- 0.08 gram of antioxidant, 2.4 grams of chain transfer agent IOTG, obtained from BASF under the trade designation "Irganox 1010 ", along with 0.34 grams of < MEHQ, and Lee. Azobis (2,4-dimethylpentanenitrile), available from DuPont Dinemoa & Company under the tradename "Bazo 52 ". The reactor was sealed, oxygen was purged using nitrogen, and then maintained at about 100 psig nitrogen pressure. The reaction mixture was heated to 60 ° C in the first stage and then allowed to polymerize adiabatically to reach a maximum of 111 ° C. When the reaction was complete, the mixture was cooled to below 50 < 0 > C.

Then, a solution of various initiators dissolved in 18.64 grams of ethyl acetate (0.80 grams of azobis (2,4-dimethylpentanenitrile), available from EI du Pont de Nemours and Company under the trade designation " 0.20 grams of 2,2'-azobis (2-methylbutanenitrile), available from E. I. DuPontinemore & Company under the trade designation "VAZO 67", from E.I. du Pont de Nemours and Company 0.20 grams of 2,2'-azobis (cyclohexanecarbonitrile), available from Elf Atochem, under the trade designation "Rufusol 101 ", obtained under the trade designation" 2,5-di- (t-butylperoxy) hexane and 0.16 grams of 2,5-dimethyl-2,5-di- (t- butylperoxy) hexane available from Elf Atochem under the trade designation " ) Hexyne-3) and 1.13 grams of IOTG were added to the product of the first step. The reactor was sealed, oxygen was purged with nitrogen, and then maintained at 100 psig nitrogen pressure. The reaction mixture was heated to < RTI ID = 0.0 > 60 C < / RTI > After the reaction reached a peak temperature of 150 캜, the mixture was heated to 170 캜, held at 170 캜 for 1 hour, and discharged into an aluminum tray for hot periods. After cooling the material, the resulting solid polymer was beat with a hammer. The molecular weight of the oligomer was determined by GPC (THF, IM di Omnisolv, 2c PL-gel-300 x 7.5 mm, polystyrene standards): Mw = 8,090, Mn = 5,824, and polydispersity of 1.39.

Oligomer Preparation Example 7

80% by weight methyl methacrylate and 20% by weight random copolymer of the preliminary Example 2

Oligomer Preparative Example 7 was prepared by the general method described in U.S. Patent No. 5,986,011 (Ellis) and oligomer Preparative Example 5 and oligomer Preparative Example 6 described above.

Examples 1 to 3

Oligomer Preparative Example 2, Oligomer Preparative Example 3, and Oligomer Each solution of Preparative Example 1 was blended into a solvent-based pressure sensitive adhesive (PSA) composition comprising 45% solids and 94/6 isooctyl acrylate / acrylic acid Respectively. A pressure sensitive adhesive composition was prepared as described in U. S. Patent RE24906. 8% active UVA in the composition was targeted. The calculated amount of the oligomer preliminary solution was added to the wet PSA in a glass jar and the contents mixed vigorously for 2 minutes with an air mixer. The crosslinking agent and other additives were not added. After mixing, the contents were allowed to stand overnight for degassing.

Exemplary Embodiment 1, Exemplary Embodiment 2, and Exemplary Embodiment 3

Solid Oligomer Preparative Example 5, Oligomer Preparative Example 6, and Oligomer Preparative Example 7, respectively, were blended into the solvent-based PSA compositions described in Examples 1, 2, Oligomer Preliminary Example 5, Oligomer Preliminary Example 6, and Oligomer Because the preliminary Example 7 is a solid, the calculations described for Examples 1, 2, and 3, except that there is no% solids calculation, Respectively. The calculated amount of oligomeric material was then placed in a separate glass jar containing excess ethyl acetate, shaken / stirred, and heated on a hot plate until the contents were visually dissolved. These contents were then poured into the PSA in a glass jar and the contents mixed vigorously for 2 minutes with an air mixer. The crosslinking agent and other additives were not added. After mixing, the contents were allowed to stand overnight for degassing.

Comparative Example 1, Comparative Example 2, and Comparative Example 3

A triazine UV absorber, available from BASF of Floham Park, NJ, under the trade designation "TINUVIN 479 ", and a benzotriazole UV absorber available from BASF under the trade designation" Tinuvin 928 " Example 2, and Example 3. < tb > < TABLE > The target amount was based on the% solids of the PSA composition. These UV absorbers were 100% active. The calculated amount was added to the PSA in the glass jar and the contents mixed vigorously for 2 minutes with an air mixer. The crosslinking agent and other additives were not added. After mixing, the contents were allowed to stand overnight for degassing.

A Nochiba coater was used to generate handspreads of each of Examples 1 to 3, Exemplary Embodiments 1 to 3, and Comparative Examples 1 to 3, respectively. The solutions described above for each of Examples 1 to 3, Exemplary Embodiments 1 to 3 and Comparative Examples 1 to 3 were poured onto a 2 mil silicone release liner, And a mill gap was set. Samples were poured out, pulled through a notch bar and placed in an oven at 200 ° F for 5 to 10 minutes, after which the liner was removed and 2 mil ETFE was hand laminated to both sides of the adhesive. Thereby, a sandwich structure with an adhesive between the films was produced. Each film was then evaluated for transmittance, haze and transparency using a Haze-Gard Plus instrument (BYK-Gardner USA, Columbia, MD). Data are shown in Table 1 below.

[Table 1]

It should be understood by those skilled in the art that various changes and modifications of the present invention can be made by those skilled in the art without departing from the scope and spirit of the present invention and that the present invention should not be unduly limited to the exemplary embodiments described herein.

Claims (15)

A composition comprising a pressure-sensitive adhesive and a blend of ultraviolet-absorbing oligomers,
The ultraviolet-absorbing oligomer may be a first divalent unit comprising a pendent ultraviolet absorbing group; And a second divalent unit represented by the formula:

[In the above formula,
R ¹ is hydrogen or methyl;
R < ² > is an alkyl having 4 to 20 carbon atoms,
Wherein the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive comprising the second divalent unit, and for at least some of the second divalent units in the pressure sensitive adhesive, R ² is the second divalent unit in the ultraviolet- Alkyl having the same number of carbon atoms as at least some of the units. 2. The composition of claim 1 wherein R < ² > is alkyl having 8 carbon atoms. The composition according to claim 1, wherein the ultraviolet light-absorbing oligomer has a number average molecular weight of 1/2 or less of the number average molecular weight of the pressure-sensitive adhesive. 2. The composition of claim 1, wherein at least one of the pressure sensitive adhesive or the ultraviolet light-absorbing oligomer comprises a pendant carboxylic acid, a hydroxyl, an aminocarbonyl, an alkylaminocarbonyl, or a dialkylaminocarbonyl group. Unit wherein the alkyl in the alkylaminocarbonyl or dialkylaminocarbonyl is optionally substituted by hydroxyl. 5. The composition of claim 4, wherein both the pressure sensitive adhesive and the ultraviolet light-absorbing oligomer comprise the same third divalent unit. The composition of claim 1, wherein the pendant ultraviolet absorber comprises triazine, benzophenone, or benzotriazole. 7. A composition according to claim 6, wherein each first divalent unit is independently represented by the formula:

In this formula,
R ¹ is independently hydrogen or methyl;
V is O or NH;
X is a bond, alkylene, or alkyleneoxy, wherein said alkylene or alkyleneoxy has from 1 to 10 carbon atoms and optionally one or more -O- groups intervened and optionally substituted by hydroxyl groups;
R is alkyl having 1 to 4 carbon atoms;
n is 0 or 1;
Z is a benzoyl group optionally substituted by hydroxyl, alkyl, halogen, or hydroxyl; A 4,6-bisthenyl [1,3,5] triazin-2-yl group wherein each phenyl is independently optionally substituted by one or more alkyl or alkoxy groups; Or a 2H-benzotriazol-2-yl group optionally substituted by one or more halogens. 8. The composition of claim 7, wherein at least some of the first divalent units in the ultraviolet light-absorbing oligomer comprise different Z groups. 8. The composition of claim 7, wherein the composition comprises different second ultraviolet light-absorbing oligomers in the blend, wherein the first ultraviolet light-absorbing oligomer in the ultraviolet light-absorbing oligomer and the second ultraviolet light- Lt; 2 > units comprise different Z groups. The composition of claim 1, wherein the ultraviolet light-absorbing oligomer is present in the composition in an amount ranging from 0.5% to 25% by weight based on the total weight of the composition. 10. An article comprising the composition of any one of claims 1 to 10, wherein the article is a photovoltaic device, a vehicle wrap, a graphic film, a construction film, or a window film. A first polymeric film substrate having a first surface and a second surface opposite the first surface;
A barrier film disposed on a first surface of the first polymeric film;
A pressure sensitive adhesive layer having a first surface and a second surface opposite the first surface, wherein a first surface of the pressure sensitive adhesive is disposed on the barrier film opposite the first polymer film substrate; And
A second polymer film substrate disposed on the second surface of the pressure-sensitive adhesive layer;
The assembly comprising:
Wherein the pressure-sensitive adhesive layer comprises an ultraviolet-absorbing oligomer,
Wherein the ultraviolet light-absorbing oligomer comprises a first divalent unit comprising a pendant ultraviolet absorber; And a second divalent unit represented by the formula:

[In the above formula,
R ¹ is hydrogen or methyl;
And R < ² > is an alkyl having 4 to 20 carbon atoms. 13. The assembly of claim 12, wherein the barrier film comprises at least a first and a second polymeric layer separated by an inorganic barrier layer. 14. The assembly of claim 12 or 13, further comprising an encapsulant layer on which the first polymeric film substrate is disposed. 15. The assembly of claim 14, wherein the encapsulant layer is on a photovoltaic cell.